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Class_XA-iliL C-b 

Book 

Gipiglit N? 



COraRIGHT DEPOSIT. 



1 




Ernest L. Ransome 

FOUNDER 



plllllllllllllllllllllllllllllllllllllllillllli 

I The Ran^ome Book 

I HOW TO MAKE AND 

I HOW TO USE 

I CONCRETE 



^/^'X Written and Compiled by 

h!" COLIN CAMPBELL, C.E., E.M. 



Director, Editorial Bureau, 
Portland Cement Association 



PRICE ONE DOLLAR 



m " Well-Mixed Concrete for Perviancnce/' m 

I Ransome: Concrete Machinery Co. 1 

M The Pioneer Builders of Concrete Machinery g 

I \\r, BROADWAY NEW YORK CITY £ 

M FA ('TO it IKS ^ 

^ I)1..\KI.M;.\, N..I. l{K.\l)lN(i. r\. t»s||K.»-;H, WIS. 

llllllllllllllllllllllllllllllllllllllllllillllll^^^ 



I A4S9 

C'5 



Copyrighted, 1917, by 
Ransome Concrete Machinery Co. 



//^ 



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e)ci.A48iir)0 
DEC 28 1917 



Form V 



^ INTRODUCTION 

V- 

r 

In issuing this booklet the Ransome Concrete 
Machinery Company is making a departure from 
usual practice that it is hoped will be popular. The 
Ransome line of machinery and concreting equip- 
ment has been subordinated to those fundamental 
practices which govern success in the use of concrete. 
The thought is this: However good the machine 
may be, the concrete cannot be all that it should be 
unless the human element can be controlled. The 
machine cannot do that. This is up to the man on 
the job. Success in the use of concrete, as in the use 
of any other building material, lies in following well- 
established rules that have proved themselves the 
proper guide. 

Concrete is too big a subject to be covered within 
the limited space of this booklet; but there have 
been gathered here useful data that are applicable to 
almost any and every kind of concrete work. Every 
page, it is believed, contains more than one reminder 
of the things that should be done but which are 
frequently overlooked or neglected. 

Among many sources of information on \\w usi^s 
of concrete are the numerous booklets and pamphlets 
issued by the Porthmd Cement Association. All of 
these publications can be obtained for Ww jiskiim. 



iv INTRODUCTION 

and a collection of tlieni forms a valuable reference 
library on good concrete practice and the many 
popular uses of concrete. It is suggested that users 
of Ransome eciuipment will find much profitable 
information in the following, copies of which may 
be had free of charge by addressing the Portland 
Cement Association, 111 West Washington Street, 
Chicago : 

Concrete Silos 

Portland Cement Stucco 

Concrete in the Country 

Farmers' Handbook on Concrete Construction 

Concrete Swimming and Wading Pools 

Concrete Linings for Irrigation Canals 

That Alley of Yours 

Concrete Houses and Why to Build Them 

Fundamentals of Reinforced Concrete Design 

How to Maintain Concrete Roads and Streets 

Recommended Specifications for Reinforced Concrete Design 

Suggested Specifications for Concrete Floors 

Why Build Fireproof? 

Integral Curb for Concrete Pavement 

Cement Stave Silos 

Concrete Tile for Land Drainage 

Protecting Concrete in Warm Weather 

Concrete Grain Bins and Elevators 

Bulk Cement 

Concrete Ships 

Facts Every One Should Know about Concrete Roads 

Standard Specifications and Tests for Portland Cement 

Specifications for Concrete Roads, Streets, and Alleys and Paving 

between Street Car Tracks. 
Concreting in Cold Weather 
Tennis Every Day on Concrete Courts 
Concrete Septic Tanks 
Concrete Fence Posts 
Small Concrete Garages 



INTRODUCTION v 

Concrete Facts about Concrete Roads 

Concrete Feeding Floors, Barnyard Pavements and Concrete Walks 

Proportioning Concrete Mixtures and Mixing and Placing Concrete 

Concrete Foundations 

Concrete Troughs, Tanks, Hog Wallows, Manure Pits, and Cisterns 

Concrete Sewers 

This booklet falls short of what we want it to be. 
It could be made better if we had the suggestions of 
our many friends. We therefore invite suggestions 
and criticism as to how it may be made of greater 
value to you, so that in future editions we can 
endeavor to more nearly approach what is impossible 
to attain — perfection. 



A TRIBUTE 

On March 5, 1917, Ernest L. Ransomo died at his 
home at Plainfield, New Jersey. 

The Ransome Concrete Alachinerj^ Co. can con- 
ceive of no more fitting place than this to pay its 
tribute to a man to whom, more than perhaps any 
other person, we owe the present-day perfection of 
concrete machiner3\ More than that, the engi- 
neering profession — the whole concrete construc- 
tion field, the cement industry — is indebted to the 
pioneering spirit which ]\Ir. Ransome displayed in 
the early years of his very active life. 

Ernest L. Ransome was truly a pioneer in the 
field of concrete construction. To him belongs the 
honor of having built the first reinforced concrete 
building and the first reinforced concrete bridge in 
the United States. Fate in part marked ^Ir. Ran- 
some for the career which he chose. His father was 
a well-known experimenter with cement, since he 
was among the first, if not the first, to perfect ways 
and means of making artificial stone. 

From 1850 to 1890 Ernest L. Ransome, who was 
then located in San Francisco, devoted his time to 
applying the manj^ discoveries he had made in the 
use of cement, that is in concrete construction, to 
work of elaborate and expensive character. His 
fame was not confined to the Pacific Coast, nor even 
to the United States, for his connection with manj^ 



A TRIBUTE vii 

societies and his contributions to the mechanical 
side of the concrete industry through numerous 
inventions which he devised, made his name a 
common one among builders throughout the world. 

Numerous patents stand to his credit. He de- 
veloped the first real machine for mixing concrete. 
The cold twisted bar, for reinforcing, of which there 
are so many tons used in concrete construction today, 
was a patent of his fertile mind. Floor systems, 
method of reinforcing, types of reinforcing materials, 
all had his deep attention and profited from his keen 
insight and extremely practical nature. Perhaps in 
his time he did more to develop methods of design, 
workmanship, etc., related to the use of concrete 
than any one contemporary with him. It can be 
said, without fear of contradiction, that in the early 
years of his life he was far in advance of his co- 
workers. Others who then used concrete, or had 
their interest drawn to its possibilities, failed to 
appreciate the true worth of the many discoveries 
which Mr. Ransome made. The construction world 
was behind him — not quite ready for his forethought 
and farsightedness. For example, as early as 1894 
he called attention to the marked influence which 
time of mixing had in increasing the strength of 
mortar. likewise he determined with accuracy, 
that has only recently been confirmed, the fact that 
there was a limit to the time of mixing which was 
profitable both from the standpoint of economy and 
the strength secured in the resulting concrete. 

Mr. Ransome designed some of the first collapsible 



viii A TRIBUTE 

steel forms for concrete tunnel lining'. No man ever 
contril)ute(l more lai-<2;ely or unselfishly to any 
similar intc^rest than d\d Mi*. Hansomc^ to the* 
advancc^nenl of concrete for buiklinf»; purposes; and 
he contril)uted with a firm faith in the building- 
material he loved. As is unfortunately too often the 
case, only when a great man has passed away is the 
full measure of his worth discovered. 

Assisted by his son, A. W. Ransome, he founded 
the Ransome Concrete Machinery Company, at 
Dunellen, New Jersej^, and at various times helped 
to organize and managed construction and con- 
tracting firms. Until the day of his death he was 
identified more or less actively with the company 
which bears his name, although in the last few years 
in more of an advisory capacity than otherwise. 

The Ransome Concrete Machinery Co. feels that 
its man}^ friends should know that the prestige and 
success which it has enjoyed is deeply founded in the 
farsightedness of Ernest L. Ransome. As mar- 
velous as the growth of the concrete industry has 
been during the last fifty years, we can confidently 
predict that the ten years ahead of us will witness 
even greater achievements; but this thought should 
not in any way dim the honor which is due to Ernest 
L. Ransome, to whom the engineering and con- 
tracting professions will always owe a debt which 
can never be fully paid. 

The Ransome Concrete Machinery 
Company. 



COJNCKETE 

HOW TO MAKE AND USE IT 



GENERAL 

Many persons are under the impression that 
Portland cement is the material most responsible for 
the success of concrete work. While it is true that a 
standard Portland cement should be used, it is 
nevertheless equally as important, and in some 
cases more important, that great care be taken in 
selecting and proportioning the aggregates, — that is, 
the sand and pebBTes^ or broken sTfttie which form the 
main bulk of concrete. Portland cement is manu- 
factured after methods so exact that quality can be 
absolutely controlled. Any one should be able to 
realize the truth of this statement, because if Port- 
land cement manufacturers did not make a product 
up to specification requirements they would soon be 
without a business. 

All standard Portland cements when they leave 
the mill are of high quality. The only thing that 
can happen to them to render them worthless is 
improper care _in_ storage. Portland cement is 
sensitive to wat^r. If it were not it would not per- 
form the function intended of it, — that is, bind the 
particles of sand and pebbles or bi-oken stone 
together into what eventually becomes stone. 

1 



2 THE RAXSOME BOOK — HOW TO 

STORAGE REQUIREMENTS 

Poi'thind ('(MiKMit should lu^'or h(* piled on tlir 
ground out on \hv jol), nor in any sIkmI where it can 
absorb dampness. Only little moisture is necessarj^ 
to spoil the cement. It will parth^ if not completely 
harden, due to this moisture, and that will make it 
unfit for use in a concrete mixture. Out on the job 
cement should be piled on boards and otherwise pro- 
tected against sudden showers. On the average job 
only so much cement should be piled out of doors 
near the work as can be used within a definite period 
of hours or the w^orking day. Any other quantity 
that may be necessary to keep near the job should 
be kept in a tight shed that will thoroughly protect 
it from moisture. 

AGGREGATES 

Many users of concrete think that bank-run 
gravel, meaning the natural mixture of sand or 
gravel with more or less foreign material as it comes 
from the gravel pit, is a suitable material for use in 
concrete. Concrete failures have resulted from 
using such unscreened material. It is not suitable 
for several reasons: It often contains more or less 
loam, cla}^, or similar foreign material. Sometimes 
the bank or deposit when opened for use is not 
stripped of the overlying soil, and as material is 
dug out of the face of the pit this soil falls down and 
becomes mixed with the bank material. Often the 
deposit contains clay or silt due to the manner in 
which the deposit was originally formed in nature. 

No concrete can be stronger than the materials of 



I 



MAKE AND HOW TO USE CONCRETE 3 

which it is composed, and foreign material, Hke clay, 
loam, or silt, prevents the cement from coming in 
contact with the surfaces of the sand and pebble 
particles, thus they cannot be bonded together. In 
other words, such foreign material acts to adulterate 
the cement. Often, also, these foreign materials have 
some free chemical in them which acts injuriously 
upon the cement and prevents it from hardening. 

Bank-run gravel usually contains twice as much 
fine material as coarse, while in the average concrete / 
mixture these proportions should be about the 
reverse. The natural run of bank gravel contains 
about forty-five per cent of voids or air spaces. In 
order to fill these and make a dense concrete, the / 
amount of sand should be about half the volume of '^ 
pebbles. If more sand than this is used, as would 
be the case when the bank-run material is employed 
exactly as coming from the pit, it is necessary to use 
a much greater quantity of cement to fill up these 
voids or air spaces so as to give the concrete the 
desired strength. This, of course, is an uneconomical 
use of cement. The amount of cement used in an 
ideal mixture, as, for example, one sack of Portland 
cement, two cubic feet of sand and four cubic feet of 
pebbles or broken stone, is sufficient, when all have 
been thoroughly mixed with the proper amount of 
water, to coat every particle of sand, thus forming a 
sand-cement mortar which will practically fill all 
voids in the pebbles or broken stone, while voids 
in the sand are filled by the cement. If, however, 
'these proportions are reversed by using \\\\co as 



4 THE RANSOME BOOK — HOW TO 

much sand as pebbles, the cement is naturally in- 
sufficient to coat the increased number of sand grains, 
not to mention fill the voids or air spaces in their 
volume. The result is a weak and porous concrete. 

Mere inspection of a gravel bank will not tell any 
one whether the sand and pebbles are in correct pro- 
portions. As a matter of fact they hardlj^ ever are. 
It is also true that no two loads of bank-run gravel 
are uniform in relative proportions of fine and 
coarse material, consequently the concrete made 
from such material is not uniform. By looking at 
an ordinary gravel bank one can see how in working 
or digging from the deposit the pebbles drift down 
the face, as it were, and become separated from the 
sand. 

SCREEN BANK -RUN MATERIAL 

To make good concrete, bank-run materials must 
be screened by separating them into at least two 
grades of material. The finer material, which is in 
the sand, is arbitrarily defined as that w^hich will 
pass through a screen having four meshes to the 
linear inch. The coarser material, called pebbles, is 
that retained on such a screen and ranging in size 
from 3^ inch upward to particles as large as can 
conveniently be used on the job in question. The 
larger sizes will vary from ^ inch for fence posts 
and other concrete products up to 1, 1}4 ^^d IJ^, or 
perhaps even 3 inches for work ranging from rein- 
forced concrete floors and w^alls to heavy and massive 
foundations, where the 3 inch particles may be used 
if the volume of them is not in excess. 



MAKE AND HOW TO USE CONCRETE 5 

SCREENING PAYS 

Many persons do not believe it is worth the 
trouble to separate bank-run material^ and when 
specifications call for a 1:2:4 mixture they think 
that one volume of cement, or one sack of cement, 
to 6 cubic feet of the natural bank-run material is 
just the same thing. In a 1:2:4 mixture the 2 cubic 
feet of sand goes to fill the voids or air spaces in the 
4 cubic feet of pebbles, so that one sack of cement, 
2 cubic feet of sand, and 4 cubic feet of pebbles or 
broken stone properly mixed make about 4.5 cubic 
feet of concrete in place. On the other hand, 6 
cubic feet of the natural bank-run material with one 
sack of cement will make little if any more than 
6 cubic feet of compacted concrete. As between 
the 1:2:4 mixture and the 1 : 6 mixture the latter is 
about one third greater in volume, yet has no more 
cement in it than the other mixture, consequently 
cannot be so strong, cannot be dense, and hence 
cannot be water-tight. More often than otherwise 
a disregard of the essentials just stated is what pro- 
duces the leaky concrete of which we frequently 
hear. It is true economy to screen bank-run material 
and reproportion the sand and pebbles in definitely 
measured volumes. 

WASHING AGGREGATES 

If aggregates contain more than a certain })(M' 
cent of sand, loam, silt, or other foreign material, 
they should be washed before used in a concrete 
mixture. Specifications for concrete work some- 



6 THE RAN HOME BOOK — HOW TO 

times vary in stating the amount of such foreign 
material that may be left in the aggregates. This 
does not mean that it is at all desirable that such 
material should be there, but it is generally believed 
that from three to five per cent will not, in most 
classes of concrete work, affect the final strength. 

A number of methods can be employed to wash 
aggregates when necessary to do so. Washing 
troughs can easily be devised and such troughs can 
be made to combine the features both of washer and 
screen. A suggestion for such a washing device is 
shown in an accompanying sketch. This trough is 
set at an angle sufficient to cause the aggregates to 
be tumbled down the trough in which when the 
right amount of water is supplied continuously at 
the upper end through a hose or otherwise, the ma- 
terial will be washed in tumbling about and the 
foreign matter will be removed and carried away 
by the water. Just before the contents leave the 
trough the sand and pebbles are separated by the 
screen fixed at the lower end of the trough. 

More elaborate washing outfits have to be installed 
at commercial gravel plants sometimes. On large 
jobs it is necessary to arrange better facilities for 
washing aggregates than are provided by the simple 
trough just suggested. 



MAKE AND HOW TO USE CONCRETE 







THE RAN SOME BOOK — HOW TO 




MAKE AND HOW TO USE CONCRETE 



Symbol 



Descn'pfion 



use, 2 - %" ' ii'/zT 



bolts )/yii-h washers 



- /^ 



/ - 



JUL. 



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- e/z" 



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H 



JIM 



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2 '' - t5'/z" 

B/n O^fes /2'' ^fS" Op ening 
Steel C/iUTes ^'^ 



Steel 



M 



M- 



lA/ooct Hopper - Sins! Uned 



Note-' Obtcfin 5f<7nc(circ^ sprockets etc near to fhe folIoiA/iny 
sizes: - 



5-1 



Sprocket - PP. 9.72' T-il \ Roller chain, pitch -'2.61" 



5-2 



>^ 2238' " =28 J le'-e'/ongreg'd. 



5-3 



'< 9.12'' " ^11 



Some Pi 



yfch 



5-4 



-30.46' n^je 



J4' 92 hng 



5-5 



785" 



-9 



5a rne pitch 



5-e 



n 24.55' .-29 { 18'- y long 



5-7 



Spur Gear »< JOeS" "^76 FaceT 



5-8 



Pinion " 



" 6.01' 



15 



3" 



Pulley - e'xSO "requires 6 " sg/e. leather belt 



B.G-1 



BevetGec^r PD.3I44 T-79 pilch I ^" bore27/e 



799 T=20 



1% 



B.G.2. 



" " " 799 T=20 " '^ ^ 

6ilt?ert Screen ^o'' Inner h^egring skirt 
i< " 54^^ No wear ma 3l<'irt 



//6 



Sc^eo 
5c"54 



10 



THE HAN SOME BOOK — HOW TO 



BILL OF MATERIAL 
FOR 

SEMIPORTABLE GRAVEL PLANT 

MACHINERY 

1 :32'-()" Inrl. Bucket l^lovator — 50 tons per hour 

1 ()()" Gilbert Screen, with inner skirt 

1 ')4" Gilbert Screen, no inner skirt 

1 22'-2 i^" turned shaft (approx. length) 

(i fixed post bearings 

1 3'-(>''xl H" dia. countershaft (approx. length) 

1 4'-0" X 2iV dia. c()unt<.^rshaft (approx. length) 

() sprockets, 1 spur gear and pinion (see Table) 

70'-0" S.B.R. 2.G1" pitch drive chain (approx.) 

1 pulley 8" face, 30" dia. 

2 steel screen chutes 

1 wood eteel-lined head hopper chute 

1 wood steel-lined team hopper 

1 8 H.P. gasoline engine 

1 centrifugal pump (cap. 300 gals, per minute, disch. pipe 4" dia.) and necessary 

pipe 
1 10 H.P. gasoline engine for pump 
4 bin gates — St'd Quadrant, 12" x IG" 
1 grizzly screen, l^^" □ openings (4'-8" x b'-A.") 



No. Pes. 



FRAMING 

Dimensions 

SUBFRAMES 



Material 



Bd. Ft. 



18 


2" X G'' X lO'-O'' 




Y. P. 


180 


9 


8" X 8" X 4'-2" 




Y. P. 


203 


G 


8" X 8'' X 4'-6'' 




Y. P. 


144 


2 


8'' X 8'' X 9'-0'' 




Y. P. 


96 


3 


8" X 12" X 9'-0" 




Y. P. 


216 


5 


8" X 12" X lO'-O" 




Y. P. 


400 


GO 


H" X G'' dowels 




Steel 




4 lbs. 


20d. nails 








12 


^" X 13" bolts and washers 






IG 


^^ X 113^'' bolts and washers 






oor 




BINS 






G 


2" X 4" X IG'-O" 




Y. P. 


64 


2 


2" X 4" X 12'-0" 




Y. P. 


16 


5 


1" X 2" X 14'-0" 




Y. P. 


12 


2 


2" X 10" X 9'-0" 




Y. P. 


30 


18 


2" X 12" X lO'-O" 




Y. P. 


360 


10 


2" X 12" X 18'-0" 




Y. P 


360 


11 lbs. 


lOd. nails 










Side ^^ 


ALLS — Gravel 




IG 


2" X 4" X 7'-10" 




Y. P. 


83 


20 


2" X 10" X 12'-0" 




Y. P. 


400 


9 lbs. 


lOd. nails 










Partition and End Wall 


— Gravel 




14 


2" X 4" X 7'-4" 




Y. P. 


74 


IG 


2"x 12" X 12'-0" 




Y. P. 


3S4 


7 lb.-. 


lOd. nails 










End and 


Side Walls - 


— Sand 




s 


2" X 4" X 7'-4" 




Y. P. 


39 


s 


2" X 12" X lOM)" 




V. P. 


IGO 


14 


2" X 4" X 7'-10" 




Y. P. 


74 


20 

113;> lbs. 


2" x|10" X lO'-O" 
lOd. nails 




Y. P. 


333 














Carried fur ward 


3,628 



MAKE AND HOW TO USE CONCRETE 



11 



BILL OF MATERIAL 

FOR 

SEMIPORTABLE GRAVEL PLANT 



Girts and Posts 

No. Pes. • Dimensions 

7 4" X V X lO'-O" 

6 6" X 6" X lO'-O" 

4 6" X 6" X 20'-()" 

4 8" X 8" X W-iV 

2 8" X 8" X 20'-()" 

4 8" X 8" X 12'-0" 

46 ^" X 9^'' bolts and washers 

68 fs" X IV bolts and washers 

116 ^" X 13 K" bolts and washers 

48 ^" xl5}4" bolts and washers 



Brought forward 3,628 

Material Bd. Ft. 



Y. P. 


93 


Y. P. 


180 


Y. P. 


240 


Y. P. 


300 


Y. P. 


214 


Y. P. 


256 



16 


3" X 4" X J^" plate 




2 


I" dia. steel rod— lO'-O" 




4 


1'' dia. steel rod — ll'-2" 




2 


V dia. steel rod— 10'-7" 

Top Frame 




2 


2" X A" X 3'-4'' 


Y. P 


1 


2" X 6" X 12'-0" 


Y. P 


2 


2" X 6" X 14'-0" 


Y. P 


3 


2" X 8" X 12'-0" 


Y. P 


4 


4" X 6" X 9'-0" 


Y. P 


2 


4" X 6" X l'-9" 


Y. P 


6 


6" X 6" X 8'-0" 


Y. P 


4 


6" X 6" X 9'-0" 


Y. P 


1 


6" X 8" X 14'-<)" 


Y. P 


1 


&" X 12" X 13'-0" 


Y. P 


2 


8" X 10" X 9'-0" 

Ys" Bolts ans Washers 
12 63^"; 4 11>^; 28 13"; 24 IVA"; 
4 153^"; 2 ^" X 24" 

Settling Tank 


Y. P 


6 


2" X 4" X lO'-O" 


Y. P. 


2 


4" X 4" X 8'-0" 


Y. P. 


2 


6" X 6" X 9'-0" 


Y. P. 


4 


6" X 8" X 9'-0" 


Y. P. 


10 


2" X 12" X 14'-0" 


Y. P. 


1 


2" X 12" X 16'-0" 


Y. P. 


lib. 


lOd. nails 





4 
12 

28 

48 

72 

7 

144 

108 

56 

78 

120 



42 
21 
54 
144 
280 
32 



Bolts and Washers 
6 j^"x8"; 6 H"xl0"; 8 ^"xl53^''; 
8 M"xl5H''; 4 Mxl7>^2'' 







T 


eam 


II 


OPPER 






2 
4 

4 
2 

9 

2 lbs. 


4"x8"x ir-0" 
8" X 8" X 2'-0" 
8" X 8" X I'-O" 
8" X 8" X 1 1'-O" 
2"x8"x 12'-0' 
20d. nails 












60 

43 
149 

lis 

144 



Total 



0,675 



12 



THE RANSOMS BOOK — HOW TO 



1 




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MAKE AND HOW TO USE CONCRETE 13 

DESIGN FOR WASHING PLANT 

Accompanying drawings suggest details for a 
semiportable gravel-screening and washing plant. 
This has been designed with a view to producing 350 
cubic yards of washed aggregates per day. An 
accompanying table gives a bill of lumber and a list 
of machinery estimated as necessary to build and 
operate this plant. Horsepower required will vary 
considerably, depending upon the design and capa- 
city of the plant. Gasoline motive power is very 
convenient, economical, and adaptable. The partic- 
ular advantages of the plant shown in this design 
are that preparation of sand and pebbles for use in 
concrete can be effectively done anywhere that neces- 
sity compels the use of a deposit that can be made 
suitable if the materials are washed and screened. 

The quantity of water required to thoroughly wash 
and size sand and pebbles in a mechanical plant of 
this kind varies from one half to one gallon per 
minute per cubic yard of material prepared per day. 
That is, if the capacity of the plant is 500 yards of 
prepared material per day, water required per minute 
will vary from 250 to 500 gallons. Such wide range 
is due to variations in the amount and nature of the 
matter to be washed out. The general operation of 
preparing sand and pebbles for use as aggregate in 
concrete consists first of excavating the material 
from the bank or elevating it from the beds of 
streams, transporting it to the washing plant, 
where it is elevated to the hopper located directly 
above suitable screens, dumping il into these screens 



14 THE RANSOME BOOK — HOW TO 

and i)layiiig upon the material water under pressure, 
which in connection with the agitation in the screens 
causes rolhng and tumbHng of materials and frees 
them of foreign matter. 

Screens used in the commercial preparation of 
aggregates can be classified as gravity, reciprocating, 
and rotary. Experience has generally proven that 
gravity screening plants are not in all cases as 
satisfactory as other types in securing • a product 
possessing all desirable qualities. This is due largely 
to the great variety of material found in different 
pits and often in different parts of the same pit. 
Reciprocating or vibrating screens generally give 
better results. Cylindrical screens are made by 
attaching perforated sheet metal or wire cloth to 
circular frames, the size of perforations being 
governed by the grading of output desired. To 
obtain material properly sized for some concrete 
construction involves coarse aggregate from 3^ to 
\]/2 ii^ch and washed sand from }^ inch to that which 
will be retained on a No. 100 mesh screen. Perfora- 
tions are in most cases 13^ inch round holes in the 
first conical screen, and ^ inch diameter in the 
next screen. Material from the last screen should 
then be discharged into a settling tank. Wherever a 
grading of material is required which lies between 
14: and 3^ inch or }4. ^^d 1 inch the material must 
pass through a screen wdth 1 inch or 3^ inch perfora- 
tions and be retained on a screen having -^ inch 
perforations. It should be remembered that unless 
a very large percentage of the material ranges from 



MAKE AND HOW TO USE CONCRETE 15 

3^ to 3^ inch or from 3^ to 1 inch, as it comes from 
the pit, the foregoing grading cannot be secured in 
the same operation that produces the coarse aggre- 
gate ranging from 3^ to 13^2 inch. When specifica- 
tions refer to material retained on a 3^ inch wire 
mesh over a circular frame of suitable diameter. 
Testing-screens of this kind are held in a horizontal 
position when the material is screened through them, 
the screen being shaken by hand enough to cause 
the material under 3^ inch to pass through the 
openings; therefore the perforations or openings in 
screens used when washing or screening materials 
on a large scale must be of such diameter as will 
produce materials conforming to those obtained by 
the hand-screen test. 

It will readily be seen that sand and some large 
aggregate can be made to pass over instead of 
through a 3^ inch mesh screen if the angle at which 
it is set and the speed of travel are made slow enough. 
Many materials have been used as aggregates in 
concrete construction. Various kinds of stone 
screenings are used at times in place of sand. In 
such cases the screenings should have the same 
sizing as would apply to natural sand. 

The particles which may be considered as dust 
should be removed by washing or otherwise. A 
particular trouble sometimes encountered with stone 
screenings, especially from certain kinds of lime- 
stone, is that the particles themselves are coated 
with a very fine dust or powder which prevents the 
cement from coming in contact with tliom and 



1() THE /.WNSOME BOOK — HOW TO 

sojiictiiiii's causes coiisidci'ahlc "hailing uj)" of (lie 
mass in the mixer. The same liolcls true of some 
kinds of coarse limestone aggregates. If this trouble 
is encountered the aggregates should ho washed. 



GRADING OF AGGREGATES 

Aggregates should be well graded. The reason for 
this can be illustrated in a simple way. If we draw 
a number of circles, say, one inch in diameter, touch- 
ing one another, it will be seen that there are spaces 
among and between them in which smaller circles 
may be drawn. After these smaller circles have been 
drawn touching the larger ones, there still will be 
spaces in which still smaller circles maj^ be drawn. 
These circles and the spaces correspond to the 
pebbles and the voids or air spaces in their bulk. It 
is necessary, therefore, that the larger particles pre- 
dominate and that the grading of the materials be 
such with respect to the quantity of smaller particles 
contained in the bulk as to reduce these voids or 
air spaces to the lowest percentage. After they have 
been so reduced by the best grading possible, the 
sand voids or air spaces are filled by using the proper 
amount of cement. 

Various tests may be made to determine the quan- 
tity or volume of voids or air spaces contained in 
any bulk of material. For great precision rather 
elaborate tests are necessary. Fairly accurate deter- 
minations ma}^ be made as follows: 



MAKE AND HOW TO USE CONCRETE 17 

FIRST METHOD 

Weigh the vessel and then fill level full with water, 
then weigh again. Call the net weight of the water 
C. Say, for example, it proves to be 80 pounds. 
Remove the water, dry and fill the vessel level full 
with the aggregate. Weigh and call the net weight 
of the aggregate B. Say this is found to be 120 
pounds. Then pour water slowly into the aggregate 
until the vessel is again level full of water. Weigh 
and call the net weight of the water and aggregate A. 
Say it is 160 pounds. Then the percentage of voids 
is 100 times the quantity ^^^, or in this particular 
case 100 times ^^, = 100 times f^ = ^-^ = 4000 
-^ 80 = 50, or 50% of voids. 

In introducing the water into the vessel containing 
the aggregate care must be taken to prevent en- 
trapping air. It is good practice, therefore, to apply 
the water all at one point along the side of the vessel. 
In determining the voids in sand or fine gravel the 
method of procedure outlined above, which answers 
for coarse aggregate, should be slightly modified. 
After determining the net weight of the water (C) 
and the net weight of the sand (B), instead of pouring 
water into the sand, the sand should be removed, the 
vessel filled about half full of water, and the sand 
poured into the water. The object of pouring the 
sand into the water is to expel the air, which is im- 
possible if the order is reversed. As most sands have 
less than fifty per cent voids the water will overflow 
the vessel before it is level full of sand. When this 
point is reached care should bo taken to koo}) tlio loss 



is THE RAXSOMK BOOK — HOW TO 

of fine particles down to a minimum. When the 
vessel is level full of sand and water and all the 
overflow of water carefull}' wiped off, the net weight 
of the sand and water is obtained and the voids 
determined as above, from the equation, per cent of 
voids = 100 times ^x-- 

SECOND METHOD 

Procure two similar vessels with flat bottoms and 
vertical sides. Fill one level full with water and the 
other with the aggregate. Dip water from the 
vessel of water into the other until it appears on the 
surface, being careful not to spill any w^ater. ]\Ieasure 
the distance between the top of the vessel and the 
surface of the water. This distance divided by the 
total depth of the vessel and multiplied by 100 gives 
the per cent of voids in the aggregate. Say we have 
a vessel 18 inches deep and after the above operation 
the surface of the water is six inches below the top of 
the vessel. This would indicate a per cent of voids of 
1^ times 100 = ^= 33^%. 

Proceed exactly as above when working with a 
coarse aggregate, but with sand start with one of the 
vessels empt}^ and the other full of water. Dip a 
little less than one third of the water from the full 
vessel into the empty one and then pour the sand 
into the vessel containing the smallest amount of 
water until it is level full of sand. If the sand has 
more than one third voids, more water will have to 
be added; if less than one third voids it might be 
necessary to dip some of the water back into the 



MAKE AND HOW TO USE CONCRETE 19 

other vessel. With this method care must be taken 
that no water is lost; always dip water from one 
vessel into the other, so that at the end all the water 
started with is in the two vessels. Measure and 
figure for voids exactly as above. 

THIRD METHOD 

Carefully measure the capacity of the vessel. Say, 
for example, it takes ninety small measures of water 
to fill the vessel level full. Empty out the water, fill 
the vessel with the aggregate, and then note how 
many small measures of water can be poured into 
the aggregate until the vessel is again level full of 
water. Suppose it requires thirty small measures to 
do this — then the per cent of voids is equal to one 
hundred times the result obtained by dividing the 
number of small measures of water added to the 
aggregate by the number of small measures of water 
required to fill the vessel; or, in this case 100 times 
•^, = •1^= 331% voids. 

When using this method to determine the voids in 
sand or fine aggregate first place a given number of 
small measures of water in the vessel, say a few less 
than one third the number, required to fill the ves- 
sel, then pour the sand slowly into the water. If 
you are able to fill the vessel with sand without 
bringing water to the surface add enough measures 
of water to do this; or if on the other hand you have 
started with too much water, dip out enough so that 
the vessel may be filled with sand without causing 
the water to overflow. Note how manv measui-es of 



20 THE RANSOM K BOOK — HOW TO 

wiiirv you slar((Hl willi and how iiian}^ wviv luUivd 
or dipped out and obtain tlie per cent of voids as 
pointed out. 

FOURTH METHOD 

The following method of determining voids applies 
to sand only and is probably the best. Fill the vessel 
with sand and let the net weight of sand equal B. 
Fill the same vessel with water and let the net 
weight of the water equal A. Then the per cent of 
voids equals 100 ^'WilF equal 100 times |^. 

Of the above methods for determining voids in 
coarse aggregate the first is the most accurate, but 
approximate results may be obtained with the others, 
the value of the determination depending upon the 
care with which the work is done. At least three 
determinations for voids should be made and the 
result averaged. 

When deciding upon a mixture bear in mind that a 
first-class concrete requires that the cement be a 
little more than sufficient to fill the voids in the sand 
and that the cement and sand mortar must a little 
more than fill the voids in the gravel or stone. This 
means that if the sand at hand contains thirty-three 
per cent of voids, one cubic foot of cement (one sack, 
ninety-four pounds) can be mixed with two and one 
half cubic feet of sand, and if the gravel or stone has 
forty-five per cent of voids, the mixture of one sack 
of cement and two and one half cubic feet of sand 
can be mixed with four cubic feet of gravel or stone. 
Such a mixture will make a good concrete, but if an 



MAKE AND HOW TO USE CONCRETE 21 

exceptionally strong, dense concrete is desired, the 
mixture — with the aggregates referred to — should 
be one sack of cement to two cubic feet of sand and 
three cubic feet of pebbles or stone. 

MISCELLANEOUS AGGREGATES 

Various kinds of stone or rock and substitutes for 
them are used in concrete work. Different authori- 
ties have given slightly varying opinions as to the 
order of preference in which certain materials used 
as aggregates stand. The following table gives the 
principal kinds that have been considered, in the 
order in which they are generally valued : 

Trap Rock 100 

Granite 90 

Quartz Gravel ....... 90 

Hard Limestone 80 

Soft Limestone ...... 75 

Slag 75 

Slate 60 

Shale 55 

Cinder 50 

Just why slate and shale should be considered it is 
hard to say, since both of these materials are of a 
form that makes them particularly unsuited for use 
as concrete aggregate. The particles are flat and 
elongated, and regardless of how well mixed with the 
sand-cement mortar of a concix^lc^ mixtuix^, c.'uinof 
l)(^ uvddv to pr()(lu(*(^ i\ (l(Mis(^ (•()n(*r(M(\ \jI\\v \i 



s\s 



22 THE RAX SOME BOOK -^^ HOW TO 

seem to show that iAag stands higher up in the Ust 
than credited in the above table. Slag in this ca^e 
means slag from blast furnace operations in smelting 
iron ore. Nearly all other slags are unsuited for use 
as concrete aggregate because of the excessive 
(juantity of free chemicals they contain and the 
injurious effect these will have upon the cement. 

FIRE RESISTANCE OF AGGREGATES 

Another thing should be borne in mind in con- 
nection with aggregates. Concrete is a great fire- 
resisting material, partly because the cement itself 
in process of manufacture has been subjected to very 
high heat. However, the cement alone will not safe- 
guard the concrete if the aggregates of which it is 
composed are not in themselves of a fire-resisting 
nature. Trap rock and slag, from the very nature of 
their origin, have been subjected to high heat, and 
are therefore good fire-resisting aggregates. Some 
gravels have good fire-resisting qualities. 

Granite, though hard, may easily be affected by 
intense heat because it tends to burst or crack. Some 
limestones are soft and become converted into lime, 
which, as every one knows, is made b}' burning lime- 
stone. Trap rock is regarded as one of the ideal 
aggregates. It is hard, and breaks into shapes that 
make a dense concrete. 

For roads and pavements which from the nature of 
their use are subjected to heavy traffic and inipact, 
the aggregates should be tough and wear resisting. 

Cinders are used to some extent in concrete work 



MAKE AND HOW TO USE CONCRETE 23 

where lightness rather than strength is required, as 
in some reinforced concrete floors. Cinders, how- 
ever, make a porous concrete. Whenever used they 
should be free from ash and particles of unburned 
coal. 

SIZE OF AGGREGATES 

The maximum size of coarse aggregate is deter- 
mined by the thickness of the section in which used. 
Aggregate particles should always be less than half 
the thickness of the wall or section being placed. A 
maximum of one third such dimension is probably 
best. In some cases this maximum cannot be used, 
because the reinforcing that must be embedded in 
the concrete and the position of such reinforcing pre- 
vent the use of such large particles. It is difficult to 
cause concrete containing too large particles of 
aggregate to settle well around reinforcing and 
everywhere adhere or bond to it. 



MIXING WATER 

A very good rule to observe in connection wdth 
water used for mixing concrete is that it be equal in 
quality to drinking water. It should be clean, free 
from vegetable and animal matter, and should not 
contain acid or alkali. If water containing alkali is 
used, the result is usually a formation on the concrete 
of a whitish deposit calUnl efIl()r(\scenco. If alkali is 
present in excessive quantities it may attVct the iinal 
strength of the concrete. 



24 THE RAN SOME BOOK — HOW TO 

PROPORTIONING CONCRETE MIXTURES 
USUAL METHODS 

For very accurate work concrete is proportioned 
after determinations have been made in a laboratory 
or otherwise to ascertain the exact quantities of each 
ingredient w^hich should be used, or which is neces- 
sary to make the mixture as dense and strong as 
possible, that is, as free from voids or air spaces. On 
nmch work such exact methods are not followed. 
Proportioning is ordinarily done by volume. One of 
the commonest mixtures used is the 1:2:4 mixture, 
which is largely employed for most reinforced con- 
crete w^ork. Some modification of proportions is 
necessary, depending upon the kind of work and the 
grading of the materials used. For example, if there 
is lack of uniformity in grading of the sand or pebbles, 
or both, and the work must be water-tight, then a 
1:2:3 mixture is much safer than a 1 : 2 : 4. A table of 
mixtures commonly used in certain classes of w^ork 
follows : 

TABLE OF RECOMMENDED MIXTURES 

1:1:1 Mixture for 

The wearing course of two-course floors subject 
to heavy trucking, such as occurs in factories, 
warehouses, on loading platforms, etc. 
I'A'.VA Mixture for 

The wearing course of two-course pavements, in 
which case the pebbles or crushed stone is graded 
from 34 to }<2 inch. 



MAKE AND HOW TO USE CONCRETE 25 

1:2:3 Mixture for 

Reinforced concrete roof slabs. 

One-course concrete road^ street, and alley pave- 
ments. 

One-course walks and barnyard pavements. 

One-course concrete floors. 

Fence posts. 

Sills and lintels without mortar surface. 

Watering troughs and tanks. 

Reinforced concrete columns. 

Mine timbers. 

Construction subjected to water pressure, such 
as reservoirs, swimming pools, storage tanks, cis- 
terns, elevator pits, vats, etc. 
1:2:4 Mixture for 

Reinforced concrete walls, floors, beams, 
columns, and other concrete members designed in 
combination with steel reinforcing. 

Concrete for the arch ring of arch bridges and 
culverts; foundations for large engines causing 
heavy loading, some impact and vibration. 

Concrete work in general subject to vibration. 

Reinforced concrete sewer pipe. 
1:21^:4 Mixture for 

Silo walls, grain bins, coal bins, elevators, and 
similar structures. 

Building walls above foundation wlion stucco 
finish will not be applied. 

Walls of i)its or basements subject to considiM- 
able exposure to moisture but practically no 
direct water pressure. 



20 THE HAN SOME BOOK — HOW TO 

Manure pits, dipping vats, hog wallows. 

Backing of concrete block. 

Base of two-course road, street, and alley pave- 
ments. 
1:2>^:5 Mixture for 

Walls above ground which arc to have stucco 
finish. 

Base of two-course sidewalks, feeding floors, 
barnyard pavements, and two-course plain con- 
crete floors. 

Abutments and wing walls of bridges and cul- 
verts, dams, small retaining walls. 

Basement walls and foundations for ordinary 
conditions where water-tightness is not essential. 

Foundations for small engines. 

1:3 :G Mixture for 

Mass concrete, such as large gravity retaining 
walls, heavy foundations and footings. 
1:13^ Mixture for 

Inside plastering of water tanks, silos, and bin 
walls, where required, and for facing walls below 
ground when necessary to afford additional pro- 
tection against the entrance of moisture. 

Back plastering of gravity retaining walls. 
1 : 2 Mixture for 

Scratch coat of exterior plaster (cement and 
stucco). 

Facing l)lock and similar concrete products. 

Wearing course of two-course walks, floors sub- 
jected only to light loads, barnyard pavements, etc. 



MAKE AND HOW TO USE CONCRETE 



27 



1:23/^ Mixture for 

Intermediate and finish stucco coats. 

Fence posts when coarse aggregate is not used. 
1:3 Mixture for 

Concrete block when coarse aggregate is not 
used. 

Concrete brick. 

Concrete drain tile and pipe when coarse aggre- 
gate is not used. 

Ornamental concrete products. 



QUANTITIES OF MATERIALS REQUIRED FOR 
VARIOUS MIXTURES OF MORTAR 
AND CONCRETE 



Mixture Materials for 
One-Bag Batch 


Resulting 
Volume in 
Cubic Feet 


Quantities of Cement, Sand, and 

Pebbles or Stone required for 

One Cubic Yard of Compacted 

Mortar or Concrete 




Ce- 
ment 
in 

Sacks 


Sand 
cu. ft. 


Peb- 
bles or 
Stone 
cu. ft. 


Mortar 


Con- 
crete 


Cen^ent 
in 

Sacks 


Sand 


Stone or Pebbles 




cu. ftJcu.yd 

1 


cu. ft. 


cu. yd. 


1:11 1 


1.5 




1.75 




15.5 


23.2 


.86 






1:2 




2.0 




2.1 




12.8 


25.6 


.95 






1:2^ 




2.5 




2.5 




11.0 


27.5 


1.02 






1:3 




3.0 




2.8 




9.6 


28.8 


1.07 






1 


2::3 




2.0 


3.0 




3.9 


7.0 


14.0 


.52 


21.0 


.78 


1 


2:4 




2.0 


4.0 




4.5 


6.0 


12.0 


.44 


24.0 


.89 


1 


2J:4 




2.5 


4.0 




4.8 


5.6 


14.0 


.52 


22.4 


.S3 


1 


2i:5 




2.5 


5.0 




5.4 


5.0 


12.5 .46 


25.0 


.92 




L::i:() 




3.0 


6 




6.4 


4.2 


12.61 .47 25.2 


.94 



28 THE 1^ AN SOME BOOK — JJOW TO 

MIXING CONCRETE 

Concrete is mixed either h}' hand or machine. 
However, on jobs of any size today hand mixing is no 
longer thought of because of the labor involved, and 
also because machine mixing is certain to produce 
more uniformly mixed concrete. There are many 
kinds of concrete mixers, but broadly speaking these 
may be classified as continuous and batch mixers. 

Continuous mixers, as the name implies, are those 
into which the separate materials are continuously 
fed and from which there is an uninterrupted stream 
of mixed concrete discharged. The idea of the con- 
tinuous mixer is good, but in practice such mixers are 
not reliable. Difference in moisture in the sand, as 
well as packing of the cement in the bin or hopper in 
which contained, is likely to cause varying quantities 
of the materials to be discharged, and therefore the 
resulting concrete will not be uniform. 

BATCH MIXERS 

Engineers now almost invariably specify that con- 
crete be mixed in one of the batch types of mixers. 
This means a mixer into which the separately meas- 
ured quantities of materials are dumped and the 
mixing completed before another supply of materials 
is put in the machine. Ransome mixers are all of the 
batch type and are recognized as the highest class of 
machines in their particular field. Every size and 
kind of mixer may be found in the Ransome line, 
each having its own particular merits with special 
reference to some particular class of work for which 
it is most suitable. 



MAKE AND HOW TO USE CONCRETE 29 

MEASURING MATERIALS 

The most convenient way of measuring the sand 
and pebbles or broken stone is to set a bottomless 
box or frame holding a definite number of cubic feet 
of material into a metal wheelbarrow and then fill 
this box to the required depth or level. Otherwise 
some type of wheelbarrow particularly devised for 
measuring aggregates may be used. It is well to 
determine by one or two test batches the amount of 
water necessary to produce the required consistency, 
then as long as the aggregates being used are the 
same in quality and moisture content the same 
measured volume of water may be used for each 
batch, thus resulting in concrete of uniform con- 
sistency. If the moisture in the sand varies or if 
more porous aggregates must be used, it then be- 
comes necessary to adjust the volume of water used 
for each batch. 

CONSISTENCY OF MIXTURES 

By far too much concrete is mixed either too wet 
or too dry. Rarely is just the right amount of water 
used. In times past the greatest fault of concrete 
construction was dry concrete. In later days and at 
the present time the fault is concrete that is too wet 
— actually sloppy mixtures. For most classes of 
work the correct amount of water is that which will 
produce a concrete of ''quaky" or jelly-like con- 
sistency. Less water can sometimes be uSed for 
foundation concrete whoi'o tlie section is massive or 



80 rilE NAXSOME BOOK — HOW TO 

whoro the wall ikhhI not be wator-ti^ht, but tlie 
quaky consistency is preferable wherever possible to 
use it. 

QUANTITY OF WATER 

In hand mixing, batches should not be larger than 
can be conveniently mixed on the platform, nor 
should the batches ever be larger than can be placed 
within thirty minutes after mixing. Water is one of 
the essential ingredients of a concrete mixture. A 
certain quantity is necessary to accomplish the 
chemical change that takes place in the cement when 
combined with water. For ease of working, a little 
in excess of the best quantity necessary may be added 
to make the mass a Uttle more plastic. There are 
differences between the opinions that engineers and 
contractors have as to the correct amount of water to 
be used in concrete mixtures, and as to the effect 
which variations in the quantity of w^ater have on 
the strength and other properties of concrete. The 
amount /of water which gives concrete of maximum 
strength results in a mix which is too stiff to be con- 
veniently used in most work. For example, in plants 
where concrete block, drain tile, and sewer pipe are 
manufactured, it is desirable for profitable output to 
use a mix containing less water than that which 
gives maximum strength. This permits molds to be 
removed within a short time and hence increases 
the output of the plant. 

The exact amount of water necessary for the 
maximum strength of concrete varies with the 
method of handling and placing concrete. The 



MAKE AND HOW TO USE CONCRETE 



31 



proper quantity of water will vary with the quantity 
of cement and the size and grading of the aggregates 
and somewhat on the nature of the aggregates. The 
water required for a sand and crushed stone aggre- 
gate is not greatly different from that required for a 
sand and cement mixture, providing the aggregates 
are similarly graded. If the aggregates are soft or 
porous a somewhat greater quantity of water wdll be 
necessary. The principal difficulty in attempting to 
state a specific quantity of water for any mixture is 
due to the fact that moisture content and physical 
characteristics of the aggregates vary. An approxi- 
mation that will help to a decision is given in the 
accompanying table. 



Mix 


Approximate Mix as 
Usually Expressed 


Water Required 

(Gallons per Sack of 

Cement) 


Coment 1 Volume of Aggre- 
1 gate after Mixirg 


Cement 


Aggregate 


Fine 


Coarse 


Minimum Maximum 


1 
1 

1 


5 

4^ 

4 

3 


1 
1 
1 
1 


2 
2 


4 
3 
3 

2K 


6 ; 6>4 

5^2 6 
5 ' bVi 



Others have stated the quantity of water required 
in a slightly different way. The quaky or jelly-like 
consistency can usually be obtained by using water 
in the proportion of one gallon to one cubic foot of 
concrete in place. Some uses of concrete require 
wetter mixtures than are described by the word 
quaky, but never should the quantity of water be 
such as to produce the sloppy consistency which may 
better be described, perhaps, as one which when 
handled on a shovel causes the pebbles to separate 
from the sand-cement moi-tai*. 



32 THE ILWSOME BOOK — HOW To 

TIME OF MIXING 

( )t' late years the tendency has been to increase the 
tiiui^ of niixin^i:. This is a very desirable trend. 
Experiments have proved cone lusi\ cly that increas- 
ing the time of mixing very greatly influences the 
strength of the resulting concrete. Of course there 
is a limit to the length of time which can be devoted 
to mixing with true economy to the work in question, 
but all concrete would be better if mixed for one and 
one half minutes than one minute or less. Frequently 
a few more turns of the drum will produce the re- 
quired consistency, which is often obtained at a 
sacrifice of strength of the concrete by using more 
water than needed and reducing the time of mixing. 

Before water is added to the materials in the drum 
it should be given a few revolutions to thoroughly 
mix the materials while dry. Then the required 
amount of water should be added and the drum 
revolved for a specified time or a specific number of 
revolutions. ]\Iany mixers have attached to them a 
water tank by means of which a measured quantity 
of water for each batch may be added to the dry 
materials. 

C'are should be taken not to place more materials 
in the drum than recommended b}^ the manufac- 
turers, as proper mixing cannot then be accom- 
plished. AATien the batch has been completely mixed 
its volume in the drum should not represent more 
than one third of the total cubic capacit}^ of the 
drum. ]\Iany contractors fail to understand mixer 
capacitj\ They do not realize how much greater 



MAKE AND HOW TO USE CONCRETE 33 

is the volume of unmixed materials as they lie in the 
drum before it has been revolved than the resulting 
volume of concrete. This is a simple matter and can 
readily be understood by recalUng statements 
previously made with reference to the voids in the 
various materials. Until the measured materials 
have been mixed they represent a volume cor- 
responding to the total number of cubic feet of the 
several materials measured separately; that is, until 
mixed a 1 :3 :5 mixture has nine cubic feet of materials. 
Just as soon as mixing begins, however, the distri- 
bution of the smaller sized particles amongst the 
larger ones commences to fill the voids or air spaces 
in the mass and considerably reduces its volume. 

FORMS FOR CONCRETE 
GENERAL 

When a batch of concrete is mixed, it must be 
placed in some kind of a form or mold that will give 
it the desired shape. Practically every class of 
concrete work requires form construction, the only 
exception to this being that sometimes concrete for 
a foundation may be placed in a trench without 
forms, providing the excavation walls are firm and 
self-supporting. For work above ground and for 
concrete objects in general some kind of forms or 
molds are necessary. 

TYPES OF FORMS 

In the average run of concrete woi'k wood foi'ins 
are used. For work such as cii'culai' tanks, silos, niul 



34 THE RANSOME BOOK — HOW TO 

other circular struct arcs, there are various t\^pes of 
metal forms on the market devised with special 
reference to \\\c classes of work above mentioned. 
There are also various types of so-called form sys- 
tems, most of which are patented and involve metal 
forms. Because of the fact that no two concrete 
structures are rarely, if ever, exactly alike, wood 
forms are used more often than metal forms. Some- 
times w^here an exceptionally smooth surface finish is 
desired, and it is also advisable to prolong the life of 
the forms so they may be used repeatedly on similar 
portions of different buildings, they are lined or 
covered inside with thin sheet steel. 

REQUIREMENTS OF WOOD FORMS 

Depending upon the nature of the work, its mas- 
siveness, and hence the volume of concrete to be sup- 
ported, forms are made of lumber varjdng from one 
inch to tw^o or three inches in thickness. This refers 
to the form sheathing itself. Braces, studs, and 
posts to which sheathing is nailed may be two by 
four inches, tw^o by six inches, or any similar dimen- 
sions that will w^ithstand the loads or strains that will 
be brought upon forms by the concrete in place before 
it has hardened and become self-supporting. 

Norway pine, spruce, and southern pine are the 
most generally used and economical form lumbers. 
Short leaf pine also makes good form sheathing. If 
spruce can be obtained it is probably the best 
material to use for studs, braces, joists, and posts, 
as it is tough under bending strains. Hemlock is too 



MAKE AND HOW TO USE CONCRETE 35 

coarse grained for sheathing and sphts easily, so is 
not rehable for heavy frame work. The hard woods, 
such as oak, are too high priced and too difficult to 
work economically. 

Form lumber should be free from imperfections, 
such as shakes, rot, and knots, especially where the 
appearance of the finished work is of importance. 
Unplaned lumber will do where the concrete surface 
is to be hidden from view, but planed lumber is 
always best because of the smoother surface finish 
that can be secured on the concrete and also because 
the concrete will stick less to the forms. Air-seasoned 
lumber is better than kiln dried. The latter will 
swell and bulge at joints, while if the lumber is green 
it will shrink very quickly in drying out, after forms 
are made^ thus opening cracks through which water 
carrying cement will leak out when the concrete is 
placed. Lumber dressed on both sides and edges 
may sometimes be necessary, because it is very im- 
portant that sheathing boards be of uniform thick- 
ness; otherwise when nailed to the studs the inside 
face of forms will be very irregular and this irregu- 
larity will be reproduced in the concrete surface, 
making it unsightly. Tongued and grooved materials 
and what is known as shiplap are often used for form 
sheathing. Beveled edge stock has its advantages, 
because if the lumber swells the edges will slip past 
each other without causing warping or bulging of 
the boards. Beveled edge stuff is usually cheaper, 
because there is less waste in manufacturing at the 
mill 



:;(i THE UASSOME HOOK — HOW TO 

SAFE LOAD FOR STUDS OR POSTS 

Posts and studs for supporting forms must l)e 
strong and stiff enough to hold them in true hne and 
to ])ro\'ont sagging under the load of concrete. The 
maximum safe load for wood posts of various lengths 
and sections is given below. Knowing the length of 
post, total weight of concrete and forms to be sup- 
ported, and the economical number of posts, the 
load per post can readily be determined. It should 
be remembered that a corner post carries over one 
fourth of the load carried by a side post and that a 
side post carries one half the load of an inside post. 

TABLE I 
Maximum Safe Load in Pounds for Wood Colimms 



Length in ft. 


4 in. 


6 in. 


Sin. 


5 


9,400 






6 


8,800 






7 


8,200 






8 


7,500 


20,700 




9 


6,800 


19,800 




10 


6,300 


18,900 


37,700 


11 




17,900 


36,400 


12 




17,000 


35,200 


14 




15,100 


32,700 


16 






30,200 


18 






27,600 


20 






25,100 



Example : 

Flat slab 14 feet by 17 feet 8 inches, weighing 
approximately 60,000 pounds, 16 posts can be spaced 
economically in four rows of 4. There will be 4 cor- 
ner posts, 8 side posts, and 4 inside posts — 16 posts. 



MAKE AND HOW TO USE CONCRETE 37 

4 corner posts carry load of 1 inside post = 1 

8 side posts carry load of 4 inside posts = 4 

4 inside posts carry load of 4 inside posts = 4 

Number posts of equal load 9 

Maximum load per post=^^^= 6,666 lb. 
Length of post 6 feet inches. 

From the table we find one 4 by 4 inch post 6 feet 
long will carry safely a load of 8,800 pounds. Since 
no timbers of less than 4 by 4 inches should be used, 
this size will be adopted. 

PLANNING FORMS ECONOMICALLY 

Considerable economy in form work results from 
carefully planning the forms before cutting lumber. 
Often form units can be planned that will serve 
repeated use on similar portions of structures other 
than the one for which first made. Any such fore- 
thought given the planning of forms will therefore 
result in final economy. For some work but little 
cutting may be required. Stock lengths can be used 
and ends allowed to hang over without causing any 
inconvenience on the job. Also, if the forms are 
planned so that few nails will be necessary to hold 
them together, less damage will be done to lumber 
when knocked apart than if tightly nailed together. 
Often screws can bo used to decided advantage 
instead of nails. 

Bolts, clamps, and various kinds of ties can also 
be used on some types of forms, Ihus making any 
permanent fastenings entirely unnecessary. Such 



38 THE RAX SOME BOOK — HOW TO 

devices where they can be used make form himber 
hist longer. The forms or the hunber can be reassem- 
bled for other forms, serving repeated use on a num- 
ber of structures and thus reducing the cost of form 
work on each job. Waste of lumber in concrete form 
work results often from allowing carpenters un- 
familiar with concrete work to make the forms. For 
important jobs quite a different kind of carpenter 
skill is required than is usually possessed by a car- 
penter whose experience has been on fine permanent 
structures built throughout or largeh' of wood. The 
experienced form carpenter bears in mind that forms 
can be designed so that some if not most of the 
lumber can be used again. Therefore he is careful 
to avoid unnecessary cutting and other damage to 
lumber. 

COST OF FORM WORK 

Straight w^alls and flat floors usually require the 
simplest tjpes of forms. In normal times such forms 
can often be built for from SIO to S20 per thousand 
feet board measure of Imnber. If there are many 
corners, openings, offsets, projections, and similar 
irregularities, to be molded in the concrete surface 
or section, there must be more cutting of lumber, 
which will correspondingh' increase the cost of forms. 
In normal times form lumber can be obtained for 
from $25 to S30 per thousand feet board measure. 
The longer it can be used the less the amount of its 
original cost will be charged to any one job. 

As has been mentioned, economj^ in cost of forms 
can often be brought about by planning unit sections 



MAKE AND HOW TO USE CONCRETE 39 

so far as possible, that is, panels which can be reset 
on the same job in similar position without altera- 
tion. This is especially true in plain wall construc- 
tion, beams, floor slabs, and columns. There are on 
the market a number of types of unit forms for 
various classes of construction. These permit 
building both solid (monolithic) and hollow walls. 
Among the common types of unit forms are those 
used for silos, arches, sewers, and box culverts. 
Many of these are adjustable so as to permit being 
used for structures of the types mentioned, having 
different dimensions. 

WETTING OR GREASING FORMS 

After forms are set up and firmly braced in posi- 
tion they should be either wet down or slightly 
greased with a mixture of linseed oil and kerosene, or 
some other application, so that concrete will not 
stick to them. Each time after use the forms should 
be thoroughly cleaned, and before again used should 
be wet down or wiped with oil immediately before 
concrete is placed in them. 

IMPORTANCE OF BRACING FORMS 

Some failures of concrete work have had their 
origin in faulty form construction. This is par- 
ticularly true of floors and arches. Form studs or 
supports were not strong enough to hold the load of 
concrete, and a gradual settlement or change in 
position of forms while the concrete has been under- 
going early hardening produced small cracks in the 



40 THE RAX SOME BOOK — HOW TO 

concrete. Tlie.se naturally increase in size just as 
soon as the structure is loaded, and frequent h^ failure 
has followed. This leads up to the subject of form 
removal. 

FORM REMOVAL 
C'oncrete failures have resulted from too early 
removal of forms. It should be remembered that 
concrete hardens quite differently under different 
weather and temperature conditions. ^Vloist, warm 
weather is most favorable to the rapid hardening of 
concrete. Cold weather retards hardening greatly, 
depending upon the degree of cold. For example, it 
might be safe to remove forms in from twenty-four 
to forty-eight hours from some piece of work in warm 
weather, while it might be necessary to leave forms 
in place for two or three weeks in cold weather. It 
is particularly important not to remove forms from 
concrete that is to be self-supporting, such as floors, 
roof slabs, and arches, until all possibility of failure 
has passed. Forms maj^ often be removed from 
vertical walls within twentj^-four hours after the last 
concrete was placed, but forms for arch rings, roof 
slabs, and floors may have to be left in place for a 
week or several weeks to make certain that the con- 
crete has properh^ hardened so as to be able to sup- 
port not onlj^ its own weight but that of any load 
that may be placed upon it immediately after forms 
are removed. No specific rule can be laid down for 
the time which must elapse before forms may safely 
be removed. This is something which only experience 
and good judgment can determine. 



MAKE AND HOW TG USE CONCRETE 41 

REINFORCING CONCRETE 

PRINCIPLES OF REINFORCING 

It is presumed that those who will read this book 
know why concrete is reinforced, therefore the sub- 
ject will not be discussed at length; an outline of the 
principles will be sufficient. Concrete is relatively 
weak in tension or in resisting strains that tend to 
pull it apart. It is also weak in resisting bending 
strains. In bearing loads that are placed directly 
upon it, concrete is very strong, that is, it has a 
great compressive strength. To take advantage of 
concrete^s full compressive strength, regardless of 
how the material may be used in any portion of a 
building, it is necessary to embed steel in it to resist 
bending or pulling strains, that is, strains of tension. 
Each concrete structure is the subject of a particular 
design, so, except as relates to some standard sections 
or portions of fixed dimensions, it is not possible to 
lay down definite rules for reinforcing concrete. 

LOCATION OF REINFORCEMENT 

In every use of reinforcement it is necessary that 
the material be placed in the concrete at some 
particular point or location to secure its full effective- 
ness. In a beam, for example, the reinforcement is 
placed along its lower section, sufficiently embedded 
in the c(jncrete to prevent injury from severe ex- 
posure to fire, for instance. Usually from one to one 
and a half inches of such pi'otection is all that is 
necessary. The principal thing to obserNi^ when 



42 THE RAN SOME BOOK — HOW TO 

placing ivinfoiviiig is to make sure that its location 
in the forms with reference to the position that it is 
to occupy in the finished concrete work is exactly in 
accordance w ith the position shown on the engineers^ 
or designers' plans from which the contractor is 
working. This is necessary for several reasons — 
protection against fire, for example — but princi- 
pally because the engineer or designer has calculated 
that the quantity and size of steel specified will best 
accomplish its purpose in the location shown for it 
on the plans. Therefore in placing concrete for 
reinforced work it is very important that the steel 
when laid in position in the forms shall not be dis- 
placed when the concrete is deposited. 

Bars and mesh used for reinforcement can be 
blocked up into proper position by placing beneath 
them small cubes of concrete which may afterward 
be left in the work. If wood blocks are used for the 
same purpose, they should subsequently be removed 
and the space which they occupied be filled with a 
good, rich sand-cement mortar. 

MATERIALS USED AS REINFORCEMENT 

Various materials are used for reinforcing con- 
crete, that is, steel is used in various forms. There 
are plain, round, and square rods, twisted square 
rods, aiKl various other types of round and square 
rods that are in different ways deformed, so to speak, 
when they are manufactured. They have lugs or 
projections molded in their surface, the idea of this 
deforming being to increase the mechanical bond 



MAKE AND HOW TO USE CONCRETE 43 

between the concrete and steel. In some cases de- 
formed bars may be best, as they are a safeguard 
when concrete has not everywhere been puddled or 
spaded to place around the bars, as it should be; 
also, when for any reason the consistency of the 
concrete is drier than would be best. In some 
cases mechanically deformed bars are a safeguard 
against slight variations in the workmanship or 
placing concrete. If, however, concrete is of correct 
consistency, and is sufficiently rich in cement, the 
natural bond between concrete and plain round or 
square rods is enough to take advantage of the safe 
elastic limit of the steel. For most work round, 
square, or twisted square rods or bars are satisfactory 
and most commonly used because easiest to obtain. 

EXPANDED METAL AND MESH FABRIC 

Other types of reinforcing used largely for certain 
classes of work, such as floor and wall construction, 
roof slabs, and for ground work for stucco, are the 
various deformed or expanded sheet metals, steel 
wire mesh, and similar fabrics. Most of these rein- 
forcing materials have unusual merits if properly 
used, and they also have a wide range of use. In a 
great many cases some one of the fabrics or expanded 
metals can be substituted for steel rods or bars, 
providing the net sectional area of the materials 
substituted is equivalent to that of the rods or bars. 

Generally speaking, the average contractor need 
consider but one grade of reinforcing steel. Tliis 
can be obtained direct from any of the steel coin- 



44 THE RAX SOME BOOK — HOW TO 

panies or through dealers in the usual variety of 
building materials. It should be remembered that 
there is a great variation in steel, tha1> is, there are 
many grades of it. Some steel is quitp like wrought 
iron, while others maj' be conipared with cast iron 
as regards brittleness. This should lead one to 
realize that not all steel is suitable for reinforcing 
concrete. Reinforcing steel should meet certain 
specifications which have been laid down by engi- 
neering societies, notably the American Society for 
Testing ^laterials. Such steel ranges in tensile 
strength from 55,000 to 70,000 pounds per square 
inch. The stocks of steel often carried bj^ hardware 
stores, and particularly by local blacksmith shops, 
are not of the desired qualit\^ for reinforcement in 
concrete, ^^^len steel of a certain tensile strength or 
having other particular qualities is called for in a 
specification the contractor or builder should make 
certain that the material he is using meets the 
requirements set forth. 

CARE OF REINFORCEMENT BEFORE USE AND 
ON THE JOB 

Reinforcing steel or other reinforcing materials 
must be handled on the job properly. The steel 
nmst be placed exactly where it belongs in the con- 
crete. Care should be taken to see that before 
placed all loose rust or mill scale is removed from it 
by brushing with wire brushes or pickling in a weak 
acid bath and then washing thoroughly with clean 



MAKE AND HOW TO USE CONCRETE 45 

water; also that it is not covered wholly or in part 
with oil or grease. Any of the foregoing will prevent 
good bond or adhesion between concrete and steel. 

Reinforcing material should not be bent suddenly. 
Various types of machines are on the market intended 
for use in cutting, bending, and otherwise shaping 
reinforcing bars according to the requirements of 
plans. Reinforcing for many members of buildings 
are often furnished completely assembled so that 
they can be readily set up in the forms. Bending 
has all been done properly and this leaves but little 
work to do on the job. If bars must be bent on the 
job, proper machines should be used for the purpose 
and the bending should be done steadily and 
gradually, so that the steel is not subjected to sudden 
jerks or twists that might tend to start a fracture at 
the point where bent and thus weaken the rein- 
forcement. 



CONVENIENT CONCRETE ESTIMATING TABLES 
AND EXAMPLES 

For convenience, concrete is usually mixed in 
batches, each requiring one sack of cement. The 
following table shows the cubic feet of sand and 
pebbles (or crushed stone) to be mixed with one 
sack of cement to secure mixtures of the different 
proportions indicated in the first column. The last 
column gives the resulting volume in cubic feet of 
compacted mortar or concrete. 



THE RANSOME BOOK — HOW TO 
TABLE No. I 




The following table gives the number of sacks of 
cement and cubic feet of sand and pebbles (or stone) 
required to make one cubic yard (twentjxseven cubic 
feet) of compacted concrete proportioned as indi- 
cated in first column. 



TABLE No. II 





MIXTURES 


QUANTITIES OF MATERIALS 






Pebbles or 


Cement in 


Sand 


Stone or 


Cement 


Sand 


Stone 


Sacks 


cu. ft. 


Pebbles cu. ft. 




1.5 




15.5 


23.2 






2 




12.8 


25.6 






3 




9.6 


28.8 






1.5 


3 


7.6 


11.4 


22.8 




2 


3 


7 


14 


21 




2 


4 


6 


12 


24 




2.5 


4 


5.6 


14 i 


22.4 




2.5 


5 


5 


12.5 


25 




3 
3 


5 


4.6 


13.8 


23 


1 


4.2 12.0 


25.2 



MAKE AND HOW TO USE CONCRETE 47 

EXAMPLE I 

How much cement, sand, and pebbles will be re- 
quired to build a feeding floor 30 by 24 feet, 5 inches 
thick? 

Multiplying the area (30 by 24) by the thickness 
in feet gives 300 cubic feet, and dividing this by 27 
gives Hi cubic yards as the required volume of 
concrete. A one-course floor should be of 1:2:3 
mixture. Table II shows that each cubic yard of 
this mixture required 7 sacks of cement, 14 cubic 
feet of sand, and 21 cubic feet of gravel or stone. 
Multiplying these quantities by the number of cubic 
yards required (11 i) gives the quantities of 
material required (eliminating fractions) as 78 sacks 
of cement, 156 cubic feet of sand, and 233 cubic 
feet of pebbles or stone. As there are 4 sacks of 
cement in a barrel, and 27 cubic feet of sand or 
pebbles in a cubic yard, we shall need a little less 
than 20 barrels of cement, 6 cubic yards of sand, 
and 9 cubic yards of pebbles or stone. 

EXAMPLE II 

How many fence posts 3 by 3 inches at the top, 
5 by 5 inches at the bottom, and 7 feet long can be 
made from one sack of cement? How much sand 
and pebbles will be needed? 

Fence posts should be of a 1 :2:3 mixture. Table I 
shows the volume of a one-sack batch of this mixture 
to be 3vo cubic feet. The volume of one concrete 
post, found by multiplying the length by the average 
width and breadth in feet (7 by I by \) is I cubic 



48 TIIK RANSOME BOOK — IK )W TO 

foot. By (livi(lin<2; ,S/*„ by ;, wo find that five posts 
can 1)0 niadc^ from ] sack of c(^ni(Mit wlien mixed 
with 2 (ail)ic fcn^t of sand and li cubic feet of 
])(4)bl(*s. 

EXAMPLE III 

What quantities of cement, sand, and i)ebl)les are 
necessary to make 100 unfaced concrete blocks, each 
8 by 8 by 16 inches? 

The product of height, width,. and thickness, all in 
feet (I by | by f^) gives iy cubic foot as the 
contents of a solid block. As the air space is usually 
estimated as 33^ per cent, the volume of concrete 
in one hollow block will be | or of or |f cubic 
foot; in 100 blocks the volume of concrete will be 
-' 1 1 -- or 393^2 cubic feet, which being divided by 27 
gives a little less than 13^2 cubic yards. Unfaced 
concrete block should be of 1:23/2-4 mixture. Table 
II shows that each cubic yard of this mixture requires 
5t\ sacks of cement, 14 cubic feet of sand, and 
22yV cubic feet of pebbles. Multiplying these quan- 
tities by the number of cubic yards required (13^^) 
gives the quantities of material required as 8| sacks 
of cement, 21 cubic feet of sand, and 331 cubic 
feet of gravel. 

EXAMPLE IV 

How many 6 foot hog troughs 12 inches wide and 
10 inches high can be made from 1 barrel of cement? 

Use a 1:2:3 mixture. Table I shows the volume of 
a 1 sack batch of this mixture to be 3^^ cubic 
feet. As there are 4 sacks in 1 barrel, a barrel of 



MAKE AND HOW TO USE CONCRETE 49 

cement would be sufficient for four times 3xir, or 
15iV cubic feet of concrete. The product of the 
three dimensions, all in feet, gives the volume of one 
trough as 5 cubic feet. However, approximately 
30 per cent of this volume is in the open water basin 
or inside of the tank, leaving 3yV cubic feet as the 
solid contents of concrete in one trough. Dividing 
15tV by 3yo, we find that 4 troughs (and a 
fraction over) can be made from 1 barrel of cement 
when mixed with 8 cubic feet of sand and 12 cubic 
feet of pebbles. 

PLACING CONCRETE 
GENERAL 

The hardening which takes place when cement 
and water are combined is noticeable within a very 
short time after a batch of concrete has been mixed. 
For this reason concrete should be deposited as 
quickly as possible after mixing. No concrete should 
be used when it is thirty minutes or more old. 

METHODS OF PLACING 

Methods of placing necessarily vary in accordance 
with the class of work and the condition under which 
it is being carried on. Concrete should be de- 
posited in a layer or layers of uniform depth, as for 
instance when a foundation wall is being built, oi- 
arrangements should be made to fill up one section 
of the forms at a time, provision being made at one 
end of the section to join the next one to it so a 
water-tight joint will result. 



:>() THE RAN SOME BOOK — HOW TO 

i\)ncvv\v for ])avoiiieiits and for floors on the 
t;roun(l is <>;onorally dumped from wheelbarrows or, 
in the c*[ise of highway pavements, is placed by a 
spout or 1)}^ means of a boom and bucket. In street 
and highwa}^ pavement work the subgrade should be 
thoroughly sprinkled before concrete is placed, so 
that the concrete will not be robbed of water. 

Where the only surface finish required is that 
obtained from contact with the forms, the concrete 
should be spaded with some chisel-edged tool used 
next to form faces so as to force back coarse particles 
of aggregate and allow the fine sand-cement mortar 
to come next to the form, thus producing a smoother, 
denser, and hence water-tight surface. 

Where surfacing mixtures are used it is necessary 
to place the facing mixture a little in advance of the 
back or center of the w^ork either by hand or by 
means of a metal septum. Then the septum is with- 
drawn and the center mass consolidated by tamping 
or spading so that it w411 thoroughly unite wdth the 
facing mixture. To best accomplish this the two 
mixtures should be of as nearly the same con- 
sistency as possible. 

Care should be taken not to dump concrete into 
the forms through too great a height. If it is dropped 
more than 6 or 8 feet the materials are likely to 
separate somew^hat in falling and this w^ill cause 
pebble pockets in the work. 

Much poor concrete w^ork has been done by placing 
concrete through spouts. In such cases elevators 
are run up towers, the concrete dumped into a 



MAKE AND HOW TO USE CONCRETE 51 

hopper connected with the spout and allowed to 
flow down through the spout into place. The object 
of such placing is to make one central plant distribute 
concrete over as large an area as possible without 
changing the location of the central plant frequently. 
Spouts are frequently made to cover too wide a 
range, with the result that they lie at too flat an 
angle and then too much water is used in the mixture 
to make the concrete travel in the spout. Spouting 
concrete into place permits rapid and economical 
placing, but the concrete must not be sloppy. Care 
should therefore be taken never to set spouts at a 
flatter angle than will carry concrete of the right 
consistency. This is usually about twenty-five 
degrees. 

Concrete is also placed by compressed air. The 
Ransome Concrete Machinery Co. manufactures a 
pneumatic placing machine for this purpose which 
has special efficiency in that it both mixes the con- 
crete and places it with force at the right consistency, 
thus practically doing away with the need of tamping 
or spading in the forms. 

Concrete should not be placed in layers deeper than 
will permit firmly consolidating it with concrete 
previously placed. Nor should the operation of 
placing be interrupted so that concrete previously 
placed has commenced to harden before that sub- 
sequently placed is put upon it. If such is the case 
the two layers cannot be made to unite thoroughly. 
Such conditions pi'oduce construction seams in the 
work, which not only weaken it but are (juilo likely 



52 THE HANSOM E BOOK — HOW TO 

to be tlic cause of leakage. When necessary to dis- 
continue concreting before forms are filled, as at the 
(Mid of the day, for instance, the top of the concrete 
last i)hiced in the forms should be roughened by 
scratching it with a stick to prepare for a good bond 
with the concrete that is to be placed later. Im- 
mediately before resuming concreting the surface of 
the old concrete should be well scrubbed and washed 
with a broom and water, and painted with a mixture 
of cement and water of about the consistency of 
thick cream, this being done immediately before 
placing new^ concrete. 

Arrangements should be made wherever possible 
to carry on continuously the concreting of tanks, 
silos, reservoir walls, and any CQncrete work that has 
to be water-tight, so as to prevent the construction 
seams mentioned. However, on some work it is 
necessary to suspend concreting each day. Then 
the work should be left roughened in the forms and 
treated as previously described. On tank work some 
have found it advisable to embed at or along the 
center line of the concrete section a strip of tin or 
sheet iron half into the concrete just placed, and half 
exposed preparatory to being covered with concrete 
the next day. Just before resuming work this metal 
strip as well as the old concrete should be painted 
with the creamy cement-water paint previously 
mentioned. 

PROTECTING THE FINISHED WORK 

Proper protection of concrete after placed is of the 
utmost importance. Concrete mixtures may have 



MAKE AND HOW TO USE CONCRETE 53 

been properly proportioned, may have been mixed 
to the correct consistency, and may have been 
properly placed, yet if the concrete is allowed to dry 
out or in any other way lose the water which was 
combined with it, the cement is deprived of the 
ingredient necessary to hardening, hence the concrete 
will lack strength and water-tightness. 

The hardening of concrete is not a drying process, 
as some people suppose. If concrete after being 
placed is left exposed to sun and wind much of the 
water necessary to its hardening is lost by evapora- 
tion. Protection is especially necessary on floors 
and walls where considerable surface area is exposed. 
It is not so necessary on mass work, since such work 
is to a certain extent self-protecting. Floors, walks, 
pavements, and like work should be protected by a 
covering of moist earth or some other moisture- 
retaining material. This should be kept wet for 
several days, when it may be removed and the con- 
crete allowed to harden naturally. The ideal con- 
ditions for hardening of concrete are warmth and 
moisture. When these two conditions are present 
the concrete hardens most uniformly. An illustra- 
tion of this is seen in the practice of ponding or 
flooding concrete road pavements immediately after 
they have hardened sufficiently to permit covering 
with water. 

Thin waU sections may be given part of the pro- 
tection needed by leaving forms in place a day or two 
longer than ordinarily would Ix^ necessary and 
wetting down the entire work several times daily. 



54 THE RAN SOME BOOK — HOW TO 

Silo and tank walls should be protected by hanging 
canvas cloth over them and keeping this wet. Stucco 
should be protected in the same manner. Indeed a 
great deal of the hair-cracking in stucco work is due 
to the almost universal practice of omitting protec- 
tion against sun and wind immediately after the 
work is finished. 

Until contractors and others realize the full im- 
portance of these protective measures there will be 
more or less concrete work that will be the subject 
of unjust criticism as far as concrete itself is con- 
cerned. 

CONCRETING IN COLD WEATHER 

Many concrete contractors now keep their plant 
operating practically twelve months a year by taking 
precautions in their concrete work to observe 
practice that makes concreting in cold weather just 
as successful as that done in warm weather. 

The principles underlying the success of concrete 
work done in cold weather are the following: 

Sand and pebbles or broken stone used must be 
free from frost or lumps of frozen materials. If there 
is frost or frozen lumps in the materials they must be 
thawed out. 

Sand and pebbles or broken stone and mixing 
water must be heated. Cement forms only a small 
bulk of the materials in a batch of concrete and need 
not be heated. 

It is necessary to mix, place, and protect the con- 



MAKE AND HOW TO USE CONCRETE 55 

Crete, so that early hardening will be complete 
before the work is exposed to freezing temperatures. 

Sand and pebbles, or broken stone, and mixing 
water should be heated so that the concrete when 
placed has a temperature of seventy-five to eighty 
degrees. 

Adding common salt to the mixing water will pre- 
vent freezing of concrete that has not hardened. 
There is a limit to the quantity of salt which may be 
used, however, as an excess will affect the final 
strength of the concrete. Salt is not desirable, as it 
simply lowers the freezing point of the mixing water. 
It does not supply what is most needed — heat and 
warmth. It delays instead of hastens hardening of 
the concrete. 

Some sands and pebbles or broken stones are 
injured by too much heat. Temperature not ex- 
ceeding 150 degrees Fahrenheit will generally be 
high enough when heating these materials. 

Concrete must be placed immediately after mixing, 
so that none of the heat will be lost before placing in 
the forms. 

Metal forms and reinforcing steel should l)e 
warmed before placing concrete. Snow and ice and 
frozen concrete remaining on the forms from pre- 
ceding work should be removed. Forms can l)e 
warmed by turning a jet of steam against them oi* by 
wetting with hot water. 

Unless the work is jii'otcH'tcMl inun(Mliat(^ly al"t(M' 
placed it will 1()S(^ inucii of \\w Inwi. Canvas concm'- 
ing, sheathing, liousing in {\\v woi'Ik, oi* hay or straw 



50 THE KAN SOME BOOK — HOW TO 

]MX)perly api)lied, will furnish protection for some 
work. Small oil or coke burning stov^es or sala- 
manders are used to supply the necessary heat in 
enclosed structures. 

Temj^eratures which may not be low enough to 
freeze the concrete may delay its hardening for some 
time. Concrete placed when the temperature is low^ 
and remains low for some time afterward will not 
be safe under load as soon as though placed during 
warmer weather. 

Concrete which freezes before early hardening has 
been completed may not be permanently injured if 
after thawing out it is not again exposed to freezing 
until hardened. However, it is best to protect the 
concrete as soon as placed, so that it will not freeze. 
Alternate freezing and thawing at comparatively 
short intervals will seriously damage concrete that 
has not hardened. Forms must not be removed 
from concrete work done during cold weather too 
early. This applies to any concrete work regardless 
of season, but is particularl}^ important in cold 
weather concreting. 

Frozen concrete sometimes very closelj^ resembles 
concrete that has thoroughly hardened. When 
frozen concrete is struck with a hammer it will often 
ring like i^roperly hardened concrete. Work should 
be carefully examined before removing forms. The 
flame of a blowtorch, a steam jet, or hot water 
ai)plied to the concrete will show whether it is 
merely frozen or has hardened. If frozen, heat will 
soften it by thawing the water contained in it. 



MAKE AND HOW TO USE CONCRETE 57 

PLACING CONCRETE UNDER WATER 

Sometimes concrete must be placed under water. 
In such cases the methods must be such that the in- 
gredients will not be separated. Some kind of a 
spout or a large pipe must be used to carry the con- 
crete to a point near the bottom of the water, the 
pipe being gradually withdrawn as the concrete is 
built up. Otherwise large buckets are used which 
are lowered to and opened at the place of deposit. 
Concrete to be placed under water should not be 
mixed too wet. Difficulty often experienced wdth 
placing concrete under water comes from lack of 
care to prevent separation of cement and aggre- 
gates. Concrete cannot be thrown on the surface 
of the water and allowed to settle through it, because 
separation of materials is then certain. 

One common and practical method of placing 
under water is to provide a closed rectangular wood 
chute or circular metal one, called a tremie. This is 
placed with one end extending into the water to the 
foundation in such a manner as to prevent concrete 
from flowing out while the chute is being filled with 
concrete. When entirely filled, it is raised slightly, 
thereby permitting the concrete to distribute itself 
and at the same time permit additional concrete 
being placed in the chute, so that depositing is con- 
tinuous and the entrance of water to the chute pre- 
vented. In large work a closed bucket with hinged 
bottom is often used. When the bucket I'eaches the 
bottom, or foundation, its bottom is ]-(^1(\is(m1 aiul 
the concrete falls into position. 



58 THE hWXSOME BOOK — HOW TO 

Concrete has been placed by first filling sacks 
which were lowered through the water to the foun- 
dation. This, however, is not good practice, as good 
bond cannot be secured through different parts of 
the foundation. When the concrete is to be deposited 
from the air bj^ a receptacle low^ered into the water, 
it should be mixed dry enough so when the gate or 
trap door of the bucket is opened the material will 
be discharged in a mass. Sometimes cofferdams are 
used to prevent current w^here the concrete is de- 
posited. The water should always be kept quiet. 
The surface of the concrete under water must be kept 
as nearly level as possible to avoid the formation of 
pockets which will retain sediment or silt. Freshly 
deposited concrete should not be disturbed. If the 
concrete is not deposited continuousl}^, all sediment 
should be removed from the surface of the concrete 
by pumping or otherwise before resuming additional 
concreting. 



ACTION OF SEA WATER ON CONCRETE 

Opinions on this subject often seem contradictory. 
However, extensive investigation of the subject has 
proved that the success of concrete in sea water 
depends largelj^, if not entirely, upon certain w^ell 
defined practice. Concrete must be dense, rein- 
forcing steel must be i)laced far enough from the 
surface so that sea water will not come in contact 
with it and start oxidization or rusting which will 
eventually cause bursting of the concrete on the 



MAKE AND HOW TO USE CONCRETE 59 

face. Rich mixtures should be used throughout, 
otherwise a rich facing mixture should be placed 
simultaneously with the mass concrete. Where dis- 
integration of concrete in sea water has been ob- 
served it has generally been proved that the concrete 
lacked density, also that disintegration was more 
marked between high and low water marks, indi- 
cating that the salts in the sea water entered the 
pores of the lean concrete and caused rupture by 
crystallizing when the water evaporated. 

The United States Bureau of Standards, Tech- 
nologic Paper No. 12, says: 

The disintegration of cement structures when 
placed in contact with sea water is a phenomenon 
which has attracted the attention of cement 
manufacturers and cement users almost from 
the first time that such material was used for 
marine construction. There are cement struc- 
tures which have withstood the action of sea 
water for years, and probably will continue to 
do so, yet there are structures which have 
failed; and it is also possible in the laboratory 
by artificial solutions to destroy almost com- 
pletely a briquette, or cube, or cylinder made of 
cement mortars or concrete. The cause of this 
disintegration is not certain, though it is almost 
universally believed that it is the reaction of 
sulphate of magnesia of the sea water with tlu^ 
lime of the cement (formed during the setting) 
and the alumina of the aluminates of the cement, 



00 THE HAS SOME BOOK — HOW TO 

resulting in the formation of hydrated magnesia 
and calcium sulpho-aluminate, which crystal- 
lizes with a large number of molecules of water. 

The other constituents both of the sea water 
and the cement are usually considered of little 
effect, though lately attention is being drawn to 
the fact that both sodium chloride and mag- 
nesium chloride rapidly attack the silicates. 

Portland cement mortar or concrete, if porous, 
can be disintegrated by the mechanical forces 
exerted by the crystallization of almost any salt 
in its pores, if a sufficient amount of it is per- 
mitted to accumulate and a rapid formation of 
crystals is brought about by drying; and as 
larger crystals are formed by slow crystalliza- 
tion, there would be obtained the same results 
on a larger scale, but in greater time, if slow 
drying were had. Porous stone, brick, and other 
structural materials are disintegrated in the 
same manner. . . . 

Properly made Portland cement concrete, 
when totally inmiersed, is apparently not sub- 
ject to decomposition by the chemical action of 
sea water. 

AMiile these tests indicated that Portland 
cement concrete exposed between tides resisted 
chemical decomposition as satisfactorily as the 
totally inunei^sed concrete, it is felt that actual 
service conditions were not reproduced, and 
therefore further investigation is desirable. . . . 

Marine construction, in so far as the concrete 



MAKE AND HOW TO USE CONCRETE fil 

placed below the surface of the water is con- 
cerned, would appear to be a problem of 
method rather than materials, as the concrete 
sets and permanently hardens as satisfactorily 
in sea water as in fresh water or in the atmos- 
phere, if it can be placed in the forms without 
undue exposure to the sea water while being 
deposited. 

CONCRETE FLOORS 
GENERAL 

Concrete floors are a type of pavement. Some- 
times they are laid on the ground, and in others, as in 
reinforced concrete buildings, are aboveground. 
Concrete floors have in instances been cause for 
complaint. One of the common objections to them 
is that under heavy traffic they '^dust" more or less. 
Dusting is the result of neglect to observe one or 
more of the fundamental requirements of concrete 
construction. Usually the concrete mixtures are 
either too wet or too dry. In the first case, finishing 
operations must be gone through several times in 
order to give the floor the desired finish. Repeated 
troweling draws too much fine cement to the surface. 
This takes the wear, and not being so resistent to 
wear as aggregate particles, comes off and causes the 
dust spoken of. Too dry a mixture lacks the quan- 
tity of water needed to transform the cement chemi- 
cally, so that it will act as the fii-m, diirahh^ hindtM" 
which it really is wIhmi i)i'()])(Mly uscmI. 



02 THE RAN SOME BOOK — HOW TO 

CAUSES OF DUSTING 

'I'he (•oiiiinon causes of dusting of concrete floors 
are : 

Too fine, dirty, or otherwise unsuitable sand. 

Too little cement in the mixture. 

Too much time allowed to elapse between mixing 
and finishing. 

Troweling at several intervals after hardening has 
commenced. 

The use of driers, and, finally 

Neglect to protect the floor (keep it moist) for 
several days after concreting has been finished. 

TYPES OF FLOORS 

Like other pavements, concrete floors may be 
either one or two course. If the floors are to be 
subjected to heavy wear, one-course construction 
with hard, tough aggregates is best. In other respects 
concrete floor construction is not unlike that follow^ed 
in building concrete w^alks, roads, or other concrete 
pavements. In one-course construction a 1:2:3 
mixture is used throughout. In two-course con- 
struction a 1:3:5 concrete is used for the base, while 
the top or wearing course consists of a 1:13^ or 1:2 
mixture. Much of the trouble in two-course work 
comes from not placing the wearing course im- 
mediately after the base is placed. Another cause 
of trouble is that the top coat is usually placed too 
wet. It should be mixed stiff enough so that the 
mixture will have to be scraped from the buckets or 
wheelbarrows. Other objections that have been 



MAKE AND HOW TO USE CONCRETE G3 

advanced against concrete floors have to do with 
their disintegration in some plants where manu- 
facturing solutions of various kinds are spilled on 
them. Concrete floors will not withstand strong 
acids, but such floors are used successfully in dairies, 
creameries, soap factories, salt works, etc. General 
experience seems to prove that inasmuch as dense 
concrete is practically impervious, none of the 
ordinary industrial solutions will injure a concrete 
floor if it is built so that maximum density of con- 
crete is secured. Concrete floors, especially above- 
ground, should be water-tight. The principles of 
water-tight construction have been given else- 
where. They consist merely of properly proportioned 
mixtures placed at the right consistency and proper 
protection of the concrete for several days after the 
work has been finished. 

CONCRETE WALKS 

Th^ principles of concrete floor construction apply 
to concrete walks. Frequently concrete walks are 
made too thin; also, they are frequently laid on 
poorly drained soil, then upheaval, due to freezing of 
water retained beneath the slabs, will mar the 
appearance of the walk, if not destroy it in part. 
Walks, floors, and pavements laid on the ground 
should be on a firmly compacted soil. If drainage is 
not good, a sub-base of clean material well compacted 
may be necessary, but in such cases the sub-bas(^ 
must be drained by tile lines, otliorwise it will act 
merely as a sump to collect and I'otain water which 



()4 THE RAN SOME BOOK — HOW TO 

will then i)1'()A'(^ as disastrous as were the whole area 
uiulrained. 

Specifications for concrete floors^ walks, roads, 
streets, and alleys, issued by the Portland Cement 
Association, and obtainable on request without cost, 
SO into details of several classes of pavement con- 
struction, so these details will not be given here. 

CONCRETE TANKS 

Concrete is used most successfully in constructing 
many kinds of tanks, employed not only as con- 
tainers for various Uquids but as silos, grain bins, 
coal pockets, and similar structures, all of w^hich can 
be regarded as tanks. 

Tanks which are to hold liquids must, of course, 
be water-tight. It is best that concreting on them 
be continuous, to prevent construction seams which 
might cause leakage. Each tank must be rein- 
forced in accordance w^ith its capacity, so that no 
standard rules can be laid dow^n for the quantity or 
spacing of reinforcing material in any such structure. 

Tanks can be either cylindrical or rectangular. 
The same principles of concrete practice apply to the 
small concrete w^atering trough or tank on the farm 
as apply to the large w^ater storage standpipe or 
reservoir. Properly proportioned mixtures, proper 
consistency, careful spading in forms, and protection 
of the finished work are all vital to success. Small 
watering troughs and tanks, such as used on the 
farm, usually have the inside faces battered or sloped 
so as to relieve pressure from ice if the water should 



MAKE AND HOW TO USE CONCRETE 65 

freeze. Tanks of large capacity can be built more 
economically if circular in shape than if square or 
rectangular. Less material, both concrete and rein- 
forcing, is required in circular structures than in 
those of other shape of like capacity. Many types of 
silo forms are particularly adapted to the con- 
struction needs of grain bins, water tanks, standpipes, 
and similar concrete structures. 

Reinforcing of tanks must be properly calculated 
and the material must be correctly placed. Pro- 
bably many tank failures have been due to improper 
reinforcing or to the use of unsuitable reinforcing 
materials. For example, old chain, wire rope, and 
similar materials are not suited for tank reinforce- 
ment, as they cannot be accurately placed in the 
forms nor kept in proper position while placing con- 
crete. However strong such reinforcing material 
may be in itself, effectiveness of it is not secured 
when used in reinforced concrete tanks or similar 
structures. For the smaller classes of concrete tanks 
steel rods or mesh fabric may be used, but in large 
grain bins and elevators and similar tanks suitable 
sizes of steel rods and bars must be used. Leaky 
water tanks result from mixtures lean in cement 
or improperly proportioned mixtures, concrete placed 
too dry or too wet, and neglect to protect the con- 
crete from drying out after the work is finished. 



GO THE RANSOM E BOOK — HOW TO 

TYPES OF SILOS 

Concrete is used for silos in the form of monolithic 
construction, concrete l)lock, and cement staves. 
The last two types of construction are essentially 
masonry work. The success of block and stave silos 
depends entirely upon the care used in making and 
laying the particular units. Concrete block and 
cement stave silos are both excellent structures if 
the block and staves have been made according to 
good concrete practice. Block and staves should 
both be steam cured. Concrete silos are a form of 
tank, and to preserve the contents should be made 
water-tight and airtight. This can readily be 
secured by using the proper mixture properly placed. 

Accompanying tables will be found convenient for 
estimating quantities of materials, also as a guide 
for reinforcing silos of various sizes both wdth mesh 
reinforcing and with rods. 



MAKE AND HOW TO USE CONCRETE 



07 



CAPACITY OF ROUND SILOS IN TONS 



Inside 






INSIDE DIAMETER 


OF 


SILO 






Height 










of Silo 


















1 




in feet. 


10 ft. 


lift. 


12 ft. 


13 ft. 


14 ft. 


loft. 


16ft. 


17ft. 


18 ft. 


19 ft. 


20ft. 22 ft. 


24 


34 


41 


49 


57 


67 


76 


86^ 98 


110 


122 






25 


36 


43 


52 


60 


71 


80 


91 1 104 


116 


129 


143 




26 


38 


46 


55 


64 


75 


85 


97 ' 110 


123 


137 


152 




27 


40 


49 


58 


68 


79 


90 


102 116 


130 


145 


160 




28 


42 


51 


61 


71 


83 


95 


109 


122 


137 


152 


169 


205 


29 


44 


54 


64 


75 


87 


100 


114 


128 


144 


160 


178 


216 


30 


47 


56 


67 


79 


91 


105 


119 


135 


151 


168 


187 


226 


31 


49 


59 


70 


83 


96 


110 


125 


141 


158 


176 


196 


237 


32 


51 


62 


74 


86 


100 


115 


131 


148 


166 


184 


205 


248 


33 


53 


65 


77 


90 


105 


121 


137 


155 


174 


192 


215 


260 


34 


56 


68 


80 


94 


109 


126 


143 


162 


181 


200 


224 


271 


35 


58 


70 


84 


98 


114 


132 


149 


169 


189 


209 


234 


282 


36 


61 


73 


87 


102 


118 


136 


155 


176 


196 


218 


243 


293 


37 


63 


76 


90 


106 


123 


142 


161 


183 


204 


227 


252 


305 


38 


66 


79 


94 


110 


128 


148 


167 


190 


212 


236 


262 


316 


39 


68 


82 


97 


115 


133 


154 


173 


197 


220 


245 


272 


328 


40 


70 


85 


101 


119 


138 


160 


180 


204 


228 


255 


282 


340 


41 


72 


88 


105 


124 


143 


166 


187 


211 


236 


262 


291 


352 


42 


74 


91 


109 


128 


148 


172 


193 : 218 


244 


270 


300 


363 


43 






113 


133 


154 


179 


201 


225 


252 


280 


310 


375 


44 






117 


137 


159 


184 


207 


233 


261 


289 


320 


387 


45 










165 1 191 


215 240 


269 


298 


330 


399 


46 










170 


197 


222 247 


277 


307 


340 


412 


47 














229 254 


285 


316 


350 


424 


48 














236 


261 


293 


325 


361 


436 


49 


















301 
310 


334 
344 


371 
382 


449 


50 


















W 










i 















()S 



Tlll<: HAN SOME BOOK — HOW TO 



TABLE OF DIMENSIONS AND MATERIALS FOR 

ROOFS FOR SILOS WITH DIAMETERS 

8 FEET TO 22 FEET 



Diam- 
eter of 
Silo 



10 ft. 
12 ft. 

14 ft. 
1() ft. 

15 ft. 
20 ft. 
22 ft. 



Vortical 


Volume 


Cement 


Sand 


Rise 


of Cone. 


Required 


Required 




in cii.yds 


barrels 


cu. yds. 


21^ ft. 


I.CdO 


2.80 


.80 


3 ft. 


2.20 


3.80 


1.10 


sy2 ft. 


2.90 


5.00 


1.50 


4 ft. 


3.80 


6.60 


2.00 


4 ft. 


4.50 


7.8 


2.60 


4 ft. 


5.40 


9.4 


2.80 


4 ft. 


6.40 


11.1 


3.30 



Stone 
Required 
cu. yds. 



14 Inch Reinforcing Rods 



1.20 
1.70 
2.20 
2.90 

3.50 
4.20 
4.90 



No. of Stock 
I Rods j Length 
[Required of Rods 



31 


12 ft. 


33 


16 ft. 


45 


16 ft. 


87 


10 ft. 


93 


12 ft. 


107 


12 ft. 


113 


14 ft. 



No. of 
Lbs. of 
Rods 



62 
^8 
120 
146 

187 
226 
265 



TABLE OF MATERIALS FOR SILO FOOTING 
AND FLOORS 







Footings 






Floors 


Footings and 
















Floor 


Silo 


Cu. 
Yds. 




1:2:3 
cu. yds 










in ft. 


Ce- 


Sand 


Gravel 


Ce- 


Sand Gravel 


Ce- 


Sand Gravel 






ment 


yds. 


yds. 




ment 


yds. yds. 


ment 


yds. 1 yds. 






bbls. 








bbls. 


' 


bbls. 




10 


2.44 


2.83 


1.27 2.10 


.70 


1.22 


.36 i .54 


4.05 


1.63 1 2.64 


12 


2.91 


3.38 


1.51 i 2.50 


1.07 


1.86 


.56 


.82 


5.24 


2.07 1 3.32 


14 


3.37 


3.91 


1.75 1 2.90 


1.51 


2.63 


.79 


1.17 


6.55 


2.54 


4.07 


16 


3.84 


4.45 


2.00 1 3.30 


2.04 


3.55 


1.06 


1.57 


8.00 


3.06 


4.87 


18 


4.31 


5.00 


2.24 3.70 


2.64 


4.59 


1.37 


2.03 


9.59 


3.61 


5.73 


20 


4.77 


5.53 


2.48 


4.10 


3.32 


5.78 


1.73 


2.56 


11.31 


4.21 


6.06 


22 


5.24 


6.08 


2.72 


4.51 


4.04 















MAKE AND HOW TO USE CONCRETE 



69 



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MAKE AND HOW TO USE CONCRETE 



71 




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72 



THE RAN SOME BOOK — HOW TO 



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MAKE AND HOW TO USE CONCRETE 



73 



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74 



TIII'J RANSOME BOOK — HOW TO 



TABLE GIVINQ LINEAL FEET OF TRIANGLE 
MESH REINFORCEMENT 



Height 

of 




Inside Diameter of Silo 




.Silo 


10 feet 


12 feet 


14 feet 


10 feet 


24 feet 


333 Style No. 6 


347 Style No. 
40 Style No. 4 


347 Style No. 6 
89 Style No. 4 


336 Style No. 
151 Style No. 4 


27 feet 


343 Style No. G 
34 Style No. 4 


357 Style No. 6 
77 Style No. 4 


357 Style No. 6 
132 Style No. 4 


346 Style No. 6 
204 Style No. 4 


30 feet 


353 Style No. 6 
64 Style No. 4 


367 Style No. 
114 Style No. 4 


367 Style No. 6 
178 Style No. 4 


405 Style No. 6 
253 Style No. 4 


33 feet 


303 Style No. 
95 Style No. 4 


377 Style No. 
150 Style No. 4 


420 Style No. 6 
221 Style No. 4 


468 Style No. 6 
302 Style No. 4 


30 feet 


373 Style No. 
125 Style No. 4 


387 Style No. 6 
190 Style No. 4 


476 Stvle No. 6 
264 Style No. 4 


527 Style No. 6 
355 Style No. 4 


39 feet 


383 Style No. 
159 Style No. 4 


433 Style No. 6 
227 Style No. 4 


529 Style No. 6 
310 Style No. 4 


586 Style No. 6 
404 Style No. 4 


12 feet 


393 Style No. 6 
189 Style No. 4 


483 Style No. 6 
264 Style No. 4 


582 Style No. 6 
353 Style No. 4 


596 Style No. 6 
506 Style No. 4 


45 feet 


434 Style No. 6 
220 Style No. 4 


530 Style No. 6 
300 Style No. 4 


638 Style No. 6 
396 Style No. 4 


606 Style No. 6 
604 Style No. 4 


48 feet 


477 Style No. 
250 Style No. 4 


570 Style No. 6 
340 Style No. 4 


648 Style No. 6 
485 Style No. 4 


619 Style No. 6 
706 Style No. 4 


51 feet 


518 Style No. 
281 Style No. 4 


626 Style No. 6 
377 Style No. 4 


658 Style No. 6 
571 Style No. 4 


629 Style No. 6 
808 Style No. 4 


54 feet 


558 Style No. 
314 Style No. 4 


636 Style No. 6 
450 Style No. 4 


668 Style No. 6 
660 Style No. 4 


639 Style No. 
900 Style No. 4 


57 feet 


599 Style No. 
345 Style No. 4 


646 Style No. 6 
527 Style No. 4 


678 Style No. 6 
746 Style No. 4 


649 Style No. 6 

959 Style No. 4 

53 Style No. 23 


m feet 


042 Style No. 
375 Style No. 4 


()56 Style No. 6 
()00 Style No. 4 


688 Style No. 6 
835 Style No. 4 


659 Style No. 6 

1008 Style No. 4 

102 Style No. 23 


Floor 


38 Style No. i\ 


48 Style No. 6 


08 Style No. 


87 Style No. 6 


Roof 


96 Style No. 6 


134 Style No. 6 


182 Style No. 


240 Style No. 



NoTK. Vav 38 in. widths of nu'.sh and laj) 2 in. or ii.se 42 in. widths and lap in. 
K«'inforc,eni('nl fiirnish:'d only in rolls l.")() ft., 20:) ft. and 300 ft. lon«. 



MAKE AND HOW TO USE CONCRETE 



75 



TABLE GIVING LINEAL FEET OF TRIANGLE 
MESH REINFORCEMENT 



Height 
of 


Inside Diameter of Silo 


Silo 


18 feet 20 feet 22 feet 

i 


24 feet 


368 Style No. 6 337 Style No. 6 362 Style No. 6 
173 Style No. 4 254 Style No. 4 279 Style No. 4 


27 feet 


433 Style No. 6 i 409 Style No. 6 372 Style No; 6 
229 Style No. 4 ; 319 Style No. 4 419 Style No. 4 


30 feet 


502 Style No. 6 [ 484 Style No. 6 382 Style No. 6 
285 Style No. 4 381 Style No. 4 558 Style No. 4 


33 feet 


568 Style No. 6 
343 Style No. 4 


556 Style No. 6 392 Style No. 6 
443 Style No. 4 698 Style No. 4 


36 feet 


636 Style No. 6 
399 Style No. 4 


566 Style No. 6 402 Style No. 6 
570 Style No. 4 ' 837 Style No. 4 


39 feet 


646 Style No. 6 576 Style No. 6 ^ 412 Style No. 6 
513 Style No. 4 697 Style No. 4 j 977 Style No. 4 


42 feet 


656 Style No. 6 
628 Style No. 4 


586 Style No. 6 
824 Style No. 4 


422 Style No. 6 
1116 Style No. 4 


45 feet 


666 Style No. 6 
739 Style No. 4 


596 Style No. 6 
951 Style No. 4 


432 Style No. 6 

1116 Style No. 4 

140 Style No. 23 


48 feet 


676 Style No. 6 

798 Style No. 4 

59 Style No. 23 


606 Style No. 6 1 442 Style No. 6 
951 Style No. 4 ! 1116 Style No. 4 
127 Style No. 23 ' 279 Style No. 23 


51 feet 


686 Style No. 6 
853 Style No. 4 
115 Style No. 23 


619 Style No. 6 452 Style No. 6 
951 Style No. 4 1 1116 Style No. 4 
254 Style No. 23 ■ 419 Style No. 23 


54 feet 


696 Style No. 6 
909 Style No. 4 
173 Style No. 23 


629 Style No. 6 465 Style No. (i 
951 Style No. 4 1116 Style No. 4 
381 Style No. 23 i 558 Style No. 23 


57 feet 


706 Style No. 6 
968 Style No. 4 
229 Style No. 23 


639 Style No. 6 475 Style No. (i 
951 Style No. 4 , 1116 Style No. 4 
508 Style No. 23 | 698 Style No. 23 


60 feet 


716 Style No. 6 649 Style No. 6 ! 485 Style No. 6 

1023 Style No. 4 951 Style No. 4 1116 Stylo No. 4 

285 Style No. 23 635 Style No. 23 837 Style No. 23 


Floor 


102 Style No. G 


125 Style No. 6 ! 154 Stylo No. (> 


Roof 


300 Style No. 4 


328 Style No. 4 | 400 Style No. 4 



NoTfc'.. Uae 38 in. ^^'i(^tll^' of niosh and hip 2 in. or ii.><o 42 in. widths and lap li in. 
HoinforceMiont furni.'-hod only in rolls 150 ft., 200 ft., :in«l 300 ft. hm^;. 



7() THE RAN SOME BOOK — HOW TO j 

RECOMMENDED PRACTICE FOR THE CON 
STRUCTION OF MONOLITHIC CONCRETE SILOS 

The following- brief summary of construction 
rcHiuir(Mn(Mils for monolithic concrete silos will serve 
as a guide for specifications. 

EXCAVATION 

Excavations should be to firm bearing soil always 
below possible frost penetration. Roots, sod, or any 
other perishable material must be removed. Soft, 
spongy spots should be excavated and refilled with 
well-compacted gravel. 

BACK FILLING 

When back filling is necessary it should be done 
after the footings have been completed and have 
thoroughly hardened and the walls have been 
finished to ground line. Provisions for draining the 
silo and for filling and emptying a tank, if such is to 
be built upon the top, should be provided for by in- 
serting the necessary plumbing. Requirements for 
cement and aggregates have been stated elsewhere 
and these apply to silo construction. Quality of re- 
infoi'cement has also been described in another 
section. Wire mesh may be used instead of rods but 
should be eciual in cross-sectional area to the rods for 
which substituted. It should be lapped not less than 
four inches on vertical laps and not less than eighteen 
inches on horizontal laps, all laps being securely 
wired together. 



MAKE AND HOW TO USE CONCRETE 77 

FORMS AND FOOTINGS 

All silos are now usually built by using some one 
of the several excellent commercial forms now on the 
market. Wall footings should be of such width that 
pressure on the soil will not exceed 3^000 pounds per 
square foot. For silos not over 40 feet high a footing 
1 foot thick and 2 feet wide will usually be sufficient. 

MIXTURES 

Wall footings should be a 1:3:5 mixture. Walls 
proper should be a 1 : 2}/^ : 4. Roofs, floors and walls, 
and floors of tanks should be a 1:2:3 mixture. A 
quaky consistency is best. 

PLACING CONCRETE AND STEEL 
REINFORCEMENT 

If steel rods are used the verticals should be 
embedded not less than one foot in the concrete 
footings. If wire mesh is used, the lower six inches 
of the first layer and the lower one foot of the ver- 
ticals should be embedded in the concrete footings. 
Concrete should be well spaded next to the forms to 
secure a smooth surface. Walls should be uniformly 
six inches thick. Reinforcing should be placed mid- 
way between inner and outer surfaces of the wall and 
thoroughly embedded. At doorway openings the 
horizontal bars, or if mesh is used, the horizontal 
wires, should be bent around vertical bars alongside 
the doorways. 

It is best that concreting of silos bo continuous, 
but frequently this is not practicable. AMion neces- 
sary to discontinue woi'k on \\\o walls, as at niti;ht, 



78 THK RANSOME BOOK — HOW TO 

the concrete should be left rough so that a good bond 
may be easily seciu'ed between fresh concrete and 
that previously placed. Sometimes a strip of sheet 
steel or galvanized iron is partly embedded in the 
concrete, and when concreting is resumed this as 
well as the surface of the old concrete is w^ell washed, 
then painted with a cement grout paint before 
concreting is continued. 

When a tank is to rest on top of the silo walls the 
first section of the tank wall should be placed at the 
same time as the floor, so as to prevent a leak at the 
point where the tank starts. Care should be taken 
not to remove forms from beneath the tank floor 
slab until all possibility of collapse has passed. 
Each tank of this kind is a subject of special design 
depending upon the capacity. 

If concreting is done in warm weather the concrete 
should be protected while hardening by frequent 
sprinkling or by some protective covering that will 
prevent rapid drying. If the work is done in cold 
weather protection should be given to prevent 
injury to the concrete from freezing, according to 
methods described elsewhere. 

ROOFS 

Many concrete buildings fall short of what they 
should be. They are finished wdth some kind of a 
roof other than concrete. Flat roofs are the simplest 
type of concrete roofs to build. They are par- 
ticularly suited to small farm buildings and other 
small structures. 



MAKE AND HOW TO USE CONCRETE 



79 



Concrete roofs must be properly designed. To a 
certain extent tables can be used for slabs of various 
thicknesses and span where only small buildings are 
involved. For larger buildings^ involving greater 
spans, roofs must be designed for the particular 
structure. 

The following table shows thickness of slab re- 
quired for concrete roofs or roof slabs of various 
dimensions from four feet square up to sixteen feet 
square : 



TABLE I 



THICKNESS OF ROOF SLABS IN INCHES 



Width in Ft. 

between 
Center Lines 

of Walls 


4 feet 


6 feet 


8 feet 


10 feet 


12 feet 


14 feet 


H) feet 



Length of Roof in Feet between Center Lines of Walls 



6 ft. 



8 ft. 10 ft. 12 ft. 14 ft. 16 ft. 



2 in. 2 in. 2}^ in. 2H in. 2^ in. 2^ in. 2K^ 



2Kin. 23/^ in. 2^ in. 3 



in. 3 in. 3 



3 in. 3}^ in. 33^ in. 3}^ in. 4 



33^ in. 4 

4 



in. 4)'2 ii^- 4} 2 

in. 4} 2 ii^- 5 

... 5 in. ;V 2 

() 



Load = weight of roof + 50 pounds per square foot. 



80 



THE RAN SOME BOOK - HOW TO 



The following table shows the amount of cement, 
sand, and i)el)l)les or l)roken stone recjuired for roofs 
of \'arious area and thickness: 



TABLE II 
CEMENT, SAND, AND STONE OR PEBBLES 

Required for Concrete Slab Roofs. Proportions for concrete 
1:2:3. Each cubic yard of 1:2:3 concrete requires about 1.74 
barrels of cement, .52 cubic yards of sand, and .77 cubic yards of 
stone. 



WIDTH OF SLAB IN FEET (BETWEEN EAVES) 







4 


6 


8 


10 


12 


14 


16 


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6 
8 
10 
12 
14 
16 


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1.7 
2.2 
2.6 
3.0 
3.5 


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2.6 
3.3 
4.7 
5.5 

6.2 


4.2 
6.1 
7.3 

8.5 
10.1 










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7.6 
10.4 
13.7 
14.4 








12.5 
16.4 
20.8 






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21.2 
26.7 


33.3 


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4 
6 
8 
10 
12 
14 
16 


1.4 
2.1 
3.4 
4.3 
5.2 
6.1 
6.9 














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3.9 
5.2 
6.5 
9.4 
10.9 
12.5 












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12.1 
14.6 
17.0 
20.2 










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15.2 

20.8 
27.3 

28.8 








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25.0 

32.8 
41.6 






5 


Si 


42.5 
53.4 


'66'6 




B S 

i'l 

o 1 
- 1 

SI 


4 
6 
8 
10 
12 
14 
16 


2.1 
3.1 
5.1 
6.5 
7.8 
9.1 
10.4 








^ u. 


5.9 

7.8 

9.8 

14.0 

16.4 

18.7 












-1 


12.5 
18.2 
21.8 
25.5 
30.3 











O f. 


22.7 
31.2 
41.0 
43.2 








1^ 


37.4 
49.1 
62.4 






3 


63.7 
80.1 


'99^8' 



MAKE AND HOW TO USE CONCRETE 



81 



The following table shows the size and spacing of 
reinforcing rods for roof slabs of various dimensions : 

TABLE III 
SPACING OF REINFORCING RODS IN INCHES 



widthjn^Ft. Length of Roof in Feet between Center Lines of Walls 

Center Ltnesr 



4 ft. 



6 ft 



8 ft. 



10 ft. 



12 ft. 14 ft. I 16 ft. 1|- 



4 feet.. 
6 feet . . 
Sfeet.. 

10 feet.. 
12 feet. . 
14 feet.. 

16 feet.. 



12 m. 
12 in. 



Qiin. 
24 in. 

6 in. 
6 in. 



8 m. 
36 in. 

4f in. 
12 in. 



8 in. 
36 in. 

4 in. 
36 in. 



8 in. 
36 in. 

4 in. 
36 in. 



8 in. 
36 in. 

4 in. 
36 in. 



11 in. 
11 in. 



91 in. 
22 in. 

8f in. 
8! in. 



NOTE— U p p e r 

figures are for cress 
reinfoi cement; 
Icwer figures for 
long reinforcement 



9 in. 
36 in. 

7f in. 
16 in. 
6i in. 
6i in. 



7f in. 
36 in. 

7 in. 
27 in. 
5f in. 
12 in. 



8 in. 
36 in. 

4 in. 
36 in. 



5^ in. 4J in. 
5i in. 8| in. 



7iin. 
36 in. 

6iin. 
36 in. 
5j in. 
16 in. 









4 in. 
4 in. J 



Load = weight of roof + 50 pounds per square foot. 



The following example shows method of using the 
three tables preceding: 

Example. Required, the thickness of slab, 
amount of concreting materials, spacing of lateral 
and transverse reinforcement, and the amount of 
reinforcing rods, for tlio flat slab roof of a building 12 



82 THE RAX SOME BOOK — HOW TO 

feet by 14 feet in outside dimensions, with 12 inch 
eaves on all sides. The size of the roof slab between 
the center lines of walls will be 13 feet (3 inches by 
11 feet 6 inches. Referring to Table I, we run down 
the vertical column at the left to the smaller dimen- 
sion of the slab, which in this case is 11 feet 6 inches. 
As this dimension is not given in the table we take 
the next larger, which is 12 feet. Running across 
horizontally to the larger dimension of the slab 
(13 feet 6 inches) we find that this is not given in 
the table, but that we must take 14 feet. In the 
square directly below 14 feet, and horizontally 
opposite 12 feet, we find the required thickness of 
the roof to be 4^ 2 inches. By reference to Table II 
the- quantities of materials required are easily 
obtained. The size of the roof over the eaves is 14 
feet by 16 feet. The table is divided into three 
parts showing respectively the amounts of cement, 
sand, and pebbles required for roofs of various sizes. 
The upper portion of the table gives the number of 
sacks of cement required and those below it give the 
number of cubic feet of sand and pebbles or stone 
necessary. By referring to the table we find that the 
roof will require about 25 sacks of cement, 53 cubic 
feet of sand, and 79 cubic feet of pebbles or stone. 

The spacing of the reinforcing rods is shown in 
Table III. As the roof is 11 feet 6 inches by 13 feet 6 
inches between center lines of walls, the next larger 
dimension shown in the table should be used. These 
are 12 feet b}' 14 feet. By running down the left 
hand vertical column to 12 feet, then running across 



MAKE AND HOW TO USE CONCRETE 83 

horizontally to the 14 foot column, we find that cross 
reinforcement (running parallel to the short sides of 
the house) should be 5% inches apart, and the 
longitudinal rods (running the long way of the house) 
12 inches apart. Round or square f inch rods should 
be used, as shown in the column to the right of the 
table. The roof being 16 feet long and 14 feet wide, 
over eaves, will require thirty-four | inch rods 14 
feet long, parallel to the short sides, and seventeen 
f inch rods 16 feet long, parallel to the long side. 

Note. The foregoing data and tables are taken from ^' Small 
Farm Buildings of Concrete," issued by the Universal Portland 
Cement Company, to whom acknowledgment is hereby made. 

FIELD PRACTICE IN CONCRETE ROAD, STREET, 
AND ALLEY CONSTRUCTION 

SPECIFICATIONS 

Concrete* pavements in the United States date 
from 1894; yet only within the past three or four 
years has the yardage of them assumed any con- 
siderable proportions. On the first of January, 1917, 
there were approximately 75,000,000 square yards of 
concrete roads, streets, and alleys in the United 
States. 

Because of the fact that methods of constructing 
concrete pavements have been developed during a 
relatively short period, there are many contractors 
and engineers who lack experience in this field of 
concrete construction. However, two National 
Conferences on Concrete Road Building, and con- 
certed work on the part of the American Concrete 



84 THE RANSOMK BOOK — HOW TO 

Institute, American Society for Testing Materials, 
the Portland Cement Association, and similar bodies, 
have resulted in specifications which, if followed, 
insure that concrete pavement will have no superior, 
if equal. The latest specifications for concrete roads, 
streets, and alleys are those adopted by the American 
Concrete Institute in 1917. These can be obtained 
from the Portland Cement Association, 111 West 
Washington Street, Chicago, and should serve as a 
guide or basis for any other specifications covering 
the class of concrete work to which they apply. 

GRADING 

For concrete pavements there must be a properly 
prepared roadbed or subgrade. Experience has 
proved that many of the cracks which develop in 
concrete pavements are due to settlement, poor 
drainage, or other unstable conditions of the founda- 
tion on which the concrete is placed. If a concrete 
pavement is to be laid directly upon an old road 
surface, this surface should be broken up several 
inches deep, so that it can be leveled and given uni- 
form compactness before any fresh material for 
filling or grading is placed. Where fills are to be 
placed, material for this purpose should be deposited 
in layers eight to twelve inches thick and rolled to 
uniform density with an eight or ten ton roller. 

FILLS 

Concrete must not be laid on fills that have not 
finished settlement. Regardless of the amount of 



MAKE AND HOW TO USE CONCRETE 85 

rolling given fills, they will not be compacted as 
solidly as will result from allowing them to stand a 
proper length of time. Material for fills should be 
placed in layers of uniform thickness and dampened 
or sprinkled preparatory to rolling. 

DISPOSING OF EXCESS MATERIALS 

In highway pavement work it will usually be found 
good practice to leave enough of any surplus material 
along the roadside to use later as a protective 
covering for the concrete to prevent rapid drying out. 

DRAINAGE 

Proper drainage of the subgrade is of great im- 
portance. Faulty drainage will result in cracked 
slabs, due either to settlement or to the heaving from 
freezing and expansion of water retained beneath the 
concrete. A poorly drained subgrade is more likely 
to heave under frost action than one well drained. 
This heaving may cause cracking of the slabs, and 
frequently slabs will fail to return to proper level, 
thus causing unequal levels at joints of abutting slabs. 

Drainage of the surface of concrete roads and 
streets is provided for by crowning the surface by 
striking off the concrete with a strikeboard cut to 
the required contour. Alley pavements are usually 
dished, that is, are lower in the center than at the 
sides, thus accomplishing the purpose of a gutter 
also. 

Side dilch(^s on concrete roads IVcMiucMitly must h(^ 
deep to insure free (h'ainage from beneatli th(^ slabs. 



86 THE RANSOM E BOOK — HOW TO 

but deep ditches are sometinieis dangerous to traffic. 
It is therefore the practice to lay tile drains in these 
trenches and to then back fill them. Tile lines for 
subgrade drainage should be laid from one to two 
feet beyond the edge of the concrete, on both sides of 
the road or street. Such lines should not be placed 
directly under the slab, because filtration of water 
through tile joints will carry away finer particles 
from the subgrade, thus causing partial undermining 
at the edges of the slab. Before digging a trench to 
lay tile, grade stakes should be located with a level 
every one hundred feet, the amount of cut being 
marked properly on the stakes. There should be no 
sags in the tile line, as these will quickly fill with silt 
and render the drain ineffective. 

AGGREGATES 

As in all concrete work, the selection of aggregates 
is important in concrete pavement construction — 
more important in some respects than in other classes 
of concrete work, because traffic subjects the concrete 
to severe impact and abrasion. It is highly im- 
portant that the sand used be composed of hard 
grains. It must be tough and durable to withstand 
the wear of traffic and the weathering action of mois- 
ture and frost. Cleanliness of aggregates is also im- 
portant. If they contain more than three per cent 
of loam, silt, clay, or other foreign material, they 
should be washed before used. Elsewhere there have 
been given details and descriptions of a suitable 
w^ashing plant for concrete aggregates. This is a 



MAKE AND HOW TO USE CONCRETE 87 

very adaptable plant on woodwork, because semi- 
portable and can be moved from one job to another. 
In many natural deposits of so-called gravel there are 
large boulders. Sometimes these form a large portion 
of the pit's output. Economy in obtaining material 
often comes from operating a suitable crusher to 
make use of all material that must be handled in 
excavating. 

COARSE AGGREGATE 
Concrete pavements are either one or two course. 
In one-course pavements the coarse aggregate should 
be hard, tough material that will neither weather nor 
wear rapidly and hence will stand up well under 
abrasion and impact of traffic. Well-graded, hard 
particles, free from flat or elongated pieces, should 
be used. There should be no soft particles nor 
lumps of clay, as these are certain to weaken the 
concrete and later develop small pit-holes or pockets 
on the surface of the pavement. Crushed stone 
should be free from coating of crusher dust. This 
has the same injurious effect as clay, silt, or other 
foreign material. Where two-course construction is 
used the coarse aggregate for the base need not be 
so hard and tough, but should be clean and well 
graded. In two-course work the aggregates of the 
wearing course should meet with all requirements 
as to toughness and hardness. 

MIXED AGGREGATE 

Successful concrete pavement work, among other 
things, requires accurately ])r()p()i'( ioncnl concriMc^ 



88 THE RAN SOME BOOK — HOW TO 

mixtures, i)r()per consistency of mixture, proper 
placing and proper protection. Bank-run material 
will not insure correct proportions of ingredients. 
The same is true of crusher-run stone. The product 
of stone crushers varies considerably as to volumes 
of the different sized particles, just as such variations 
occur in natural deposits of gravel. Artificially 
mixed or mixed-at-the-plant aggregates, even though 
they may have been properly proportioned at the 
plant, should not be used for concrete pavements, 
because in transporting and otherwise handling from 
plant to job the sizes will become unmixed, so to 
speak; that is, one batch is certain to have too 
much fine aggregate while another will contain too 
much coarse aggregate. 

AGGREGATES FOR WEARING COURSE OF 
TWO-COURSE PAVEMENT 

The aggregates most commonly used for the 
wearing course of two-course concrete pavements are 
obtained from crushed granite or trap rock. There 
are two sizes of such material suitable for use. 
Where the best quality of material is available, 
either M to 3^ inch or 3^ to 1 inch grading may be 
used, depending upon which proves the more 
economical. If the available material is not of first- 
class qualitj^ the \i to 1 inch grading is preferable. 
No intermediate sizes in this material should be 
remoN'cd. 



MAKE AND HOW TO USE CONCRETE 89 

HANDLING MATERIALS ON THE JOB 
CEMENT 

Cement must be so stored as to prevent injury 
from dampness. A tight building, with tight floor 
raised aboveground so that free circulation of air will 
prevail around piles, is necessary. Out on the job, 
cement should never be piled on the ground even for 
a short time. Board platforms should be im- 
provised. Covering should be available to protect 
the piles against sudden showers. Waterproof 
tarpaulins or canvas are satisfactory for this purpose. 
On many concrete jobs, and particularly on concrete 
pavement work, no end of carelessness prevails in the 
handling of sacks. They cost money, are charged to 
the contractor, and unless he is able to return all 
charged to him, he is out at least ten cents for every 
sack which cannot be accounted for. A wet sack is 
worthless, and if a sudden shower comes up hundreds 
of dollars' worth of sacks may be damaged in a 

minute. 

AGGREGATES 

Usually out on the job aggregates are dumped in 
piles along the subgrade, — fine aggregate on one 
side, crushed stone or pebbles on the other. The 
following table shows the quantities of materials 
required for concrete pavement of the width and 
thicknesses indicated, and will be found convenient 
when estimating the quantities of aggregates that 
are to be distributed along the work. 

There is always possibility of considerable dirt or 
refuse becoming mixed with the aggregates when 



90 



THE RANSOME BOOK — HOW TO 



QUANTITIES OF MATERIALS REQUIRED FOR 

LINEAR FOOT OF CONCRETE PAVING FOR 

THE WIDTHS AND THICKNESSES AT 

SIDES AND CENTER AS SHOWN 



Width 


1 

Thickness 
Side and 
Center 
(inches) 


CEMENT 

(bbls.) 


SAND 

(cu. yards) 


Rock or Pebbll> 
(cu. yards) 


(feet) 


1:2:3 


l.VA-.S 


1:2:3 


1:1^:3 


1:2:3 


1:1^:3 


9 


6-7 


0.32 


0.35 


0.10 


0.08 


0.14 


0.16 


16 


6-8 


0.63 


0.68 


0.19 


0.15 


0.28 


0.30 


18 


6-8 


0.71 


0.77 


0.21 


0.17 


0.32 


0.34 


20 


6-8^ 


C.82 


0.90 


0.24 


0.20 


0.36 


0.40 


24 


6-9 

1 


1.01 


1.10 


0.30 


0.24 


0.45 


0.49 



aggregate. 

they are dumped in piles along the work as above 
mentioned. Ballast forks are commonly used for 
handling broken stone and thus prevent admixture 
of dirt with coarse aggregate. In shoveling sand 
from piles there is some waste if the piles are not 
cleaned up, while if they are cleaned up there is cer- 
tain to be some dirt mixed with the sand. Some 
contractors lay planks across the subgrade to dump 
materials on to prevent loss and also prevent the 
materials from becoming mixed with dirt. 

WATER 

Elsewhere, under the subject of ^^ Estimating for 
the Contractor/^ the quantity of water likely to be 
required in concrete pavement construction has been 
stated, as well as its probable cost. Sometimes on 
concrete road work the only source of water supply 
may be several miles distant from the job. In such 



MAKE AND HOW TO USE CONCRETE 91 

case a pumping plant is necessary and usually proves 
the most economical way of securing a dependable 
water supply. A pump capable of delivering from 
1,500 to 2,000 gallons per hour is necessary. If the 
source of supply is a stream or pond, the intake pipe 
of the pump must be protected by a cage or similar 
device that will prevent weeds, sticks, and other 
foreign material being drawn into the pipe line and 
clogging it. 

JOINTS 
Joints are placed in concrete pavement to provide 
for volume changes in the concrete owing to varia- 
tions in moisture content and in temperature. 
Engineers are not in thorough accord as to the 
distance which such joints should be spaced from 
each other. Some are disposed to omit a made 
joint entirely, depending on the concrete to crack at 
certain intervals, as it surely will. However, these 
cracks are not straight across the pavement and 
therefore are unsightly and more difficult to keep in 
good repair. For this reason the made joint is 
preferable. Engineers are also not in accord as to 
whether joints should be protected or unprotected, 
that is, whether there should be placed in the con- 
crete at each end of every slab a metal protection 
plate with joint filling material between, or whether 
the metal plate should be omitted and merely the 
prepared joint filler used. In general, joints should 
l)e not more than ^^ inch wide. Clreater widtli is 
likely to cause increased wear due to impact of steel- 
tired wheels crossing the joints. 



92 THE RAXSOME BOOK — HOW TO 

Steel ])rotectioii plates are set in place by means of 
an installing device. With some types of plate this 
device may be used also as a template to test the 
correctness of its curvature. WTiere plates are used 
it is very necessary that they be carefully set and 
that the pairs be of the same curvature. Otherwise 
joints will be low or high or otherwise uneven owing 
to the difference in curvature of the protection 
plates. Where protection plates are not used, com- 
mon practice is to allow the felt joint filler to extend 
slightly above the surface of the pavement. This 
projecting portion is then soon beaten down or 
^^ ironed out^^ by traffic. To provide for this, the 
strips of filler used should be one half inch wider 
than the greatest thickness of the slabs. 



FINISHING PAVEMENT SLABS AT JOINTS 

The surface of the pavement at joints should be 
exactly the same level on both sides of a joint and 
should also be flush with the protection plate, if 
plates are used. Otherwise there will be impact and 
consequent w^ear caused by traffic when crossing the 
joint. When finishing the concrete at joints where 
steel protection plates are used, the surface as left 
by the strikeboard should first be tested by the 
finisher with a light straightedge about four feet long, 
placed longitudinally with the road, to see whether 
the concrete is flush with the top of the plate on both 
sides of the joint, also to see whether there is enough 
concrete on both sides. If the plates are slightly 



MAKE AND HOW TO USE CONCRETE 93 

higher than they should be, a httle extra concrete 
should be spread along the joints and struck off with 
the straightedge until the surface is correct. At 
unprotected joints where the filler is allowed to pro- 
ject above the surface a split float is used to finish 
on opposite sides of the filler. This is simply a 
double wood float so made that the felt filler may 
project into the space between the two halves or 
pieces jof the float, thus allowing the surface on each 
side of the joint filler to be finished to exactly the 
same level. 



REINFORCEMENT FOR CONCRETE PAVEMENTS 

Common practice is to omit reinforcement in 
pavements under twenty feet wide. Over that width, 
however, reinforcement should be specified, and it 
would be desirable to use it even in the narrower 
widths. Mesh reinforcement is the material com- 
monly used. The heavy wires should run per- 
pendicular to the center line of the pavement. Each 
strip should be carefully lapped so as to develop the 
full strength of the metal. Specifications require 
that reinforcement shall come to within two inches 
of joints and shall not be less than two inches from 
the surface of the pavement. In placing the mesh in 
the concrete, strips should be rolled out across the 
base concrete and then turned over to prevent them 
from curhng up at the ends. To prevent any ten- 
dency to bulge upward after the mesh has been laid, 
it should be struck at various j)()ints with the corner 



04 THE RAXSOME BOOK — HOW TO 

of a shovel. This will put small kinks in the wires, 
tending to cause the mesh to lie flat and also embed 
it slightly in the base course, thus making it easier to 
place the top concrete. Before placing the top, the 
work should be examined to make certain there are no 
pockets or footprints beneath the reinforcement, as 
sometimes the mesh will prevent these from being 
filled when the top course concrete is placed. These 
spots then become a source of weakness. ^ 

FORMS 

Forms for concrete pavement work may be of wood 
or steel. There are various types of commercial 
metal forms, all having certain points in common. 
When wood forms are used the}^ should be made of 
at least two-inch stock, free from large knots and of 
straight-grained lumber, which will not tend to warp 
in use. The top edge of wood forms should be pro- 
tected with metal plates to prevent rapid wear, also 
to preserve regularity of top line, as the top edge of 
side forms serve as a guide for the strikeboard and 
any irregularities in it will be imparted to the pave- 
ment surface. Aletal protection for wood side forms 
may best be of light steel angles. These tend to 
stiffen the planks and hence make them easier to 
keep in line. Iron stakes or pins will be found better 
and more economical in the long run than wood 
stakes for holding forms in line. Steel stakes should 
be ^ or I inch stock. Lighter ones tend to bend 
under repeated driving. 



MAKE AND HOW TO USE CONCRETE 95 

MEASURING MATERIALS 

Materials must be carefully measured so that 
correct proportions will always be used. Careful 
measuring also results in economy of materials. If 
wheelbarrows are used for measuring materials they 
should be of a type intended for that purpose and of 
a known definite capacity when properly struck off 
level full. 

MIXING 

No other single operation of concrete pavement 
work is more often slighted than mixing of the 
concrete. Attempt to speed up the work results in 
shortening the time of mixing. Today the tendency 
is to increase time of mixing, since it has been 
proved that up to a certain limit — other things 
being equal — longer mixing has great influence on 
the strength, wearing qualities, and other desirable 
properties of the concrete. Some mixer manufac- 
turers make extravagant claims that, owing to the 
particular construction of their machine, its efficiency 
is greater than others and therefore concrete need be 
mixed only for a very short time. Statements of 
this kind are likely to be misinterpreted. Definite 
time of mixing or number of revolutions known to be 
the equivalent of a certain time should govern. 
The efficiency of a mixer is considerably lowered if 
the interior blades, vanes, or other stirring devices 
are allowed to become coated with hardened con- 
crete. This means that a mixer should be carefully 
cleaned and washed each time when leaving off 



90 THE IMXSOME BOOK — HOW TO 

work. Ev(Mi with such precautions taken some 
hardened concrete will collect in the drum, but it 
sh )uld be removed at frequent and regular intervals. 
Of late years the tendency has been to mix all con- 
crete too wet. This is objectionable on any work, 
but particularly so on concrete pavement construc- 
tion, where highest resistance to abrasion is required. 
Concrete should be mixed to a consistency which is 
difficult to work under the strikeboard. Such a 
mixture can be properly consolidated on the roadbed 
and can be struck off and finished to better advantage 
than wetter mixtures. The concrete should be stiff 
enough to hold its shape when struck off. 

PLACING CONCRETE 

The subgrade or sub-base should be sprinkled be- 
fore concrete is placed, to prevent it from absorbing 
from the concrete water necessary to its proper 
hardening. Concrete paving mixers are equipped 
either with chute or with boom and bucket for 
depositing the concrete in place. Either tj^pe will 
give satisfactory results. Where a mixer with 
chute is used, however, the chute must not be placed 
at so flat an angle that it is necessary to use too w^et 
a concrete to cause the mixture to flow down the 
chute and into place. This objection is overcome 
by mounting the drum so high that the chute need 
not lie at an angle too flat to carry concrete of 
correct consistency. 

In planning work involving paving, the greatest 
progress will be made if the work is arranged so that 



MAKE AND HOW TO USE CONCRETE 97 

the mixer will travel up grade. This allows laborers 
to wheel materials down hill to the mixer, and also 
helps the finishers, as any excess of water from the 
concrete will run away from them onto the portions 
of the pavement which have hardened. If the mixer 
is working down grade the materials must be wheeled 
up hill to it. This makes more work, not to mention 
unsatisfactory conditions for finishing. 

STRIKING OFF AND FINISHING PAVEMENT 
SURFACE 

A template or strikeboard cut to the desired 
crown of the finished pavement is the most satis- 
factory device for obtaining the required preliminary 
surface contour. The strikeboard consists simply of 
a plain or built-up plank from two to three inches 
thick. On the bottom it is cut to the proper crown 
of the pavement and usually has a strip of iron 
fastened to the striking face to prevent rapid wear. 
Strikeboards should be heavy enough to prevent 
them from riding up over the concrete. Where the 
ends slide on the side forms or curbs, they should be 
provided with a bearing piece about eight inches 
wide to prevent them from tipping and moving 
forward and so causing irregularities in the surface. 

Several combined paving gages and striking and 
finishing machines are on the market. Each of these 
has its particular points of merit. 

Late practice in concrete pavement finishing has 
practically done away with hand floats except for 
some touching up at joints. One of the latest 
methods of finishing is to use first a light steel roller 



98 TIIK RAXSOMK HOOK — HOW TO 

of a type which was first used in finishing concrete 
street pavement in Macon, (Jeoi'gia. This roller has 
become conunercially known as the Macon Concrete 
Paving Roller. 

Those unfamiliar with the Macon method of finish- 
ing concrete pavements will be interested in knowing 
its particular advantages. Any one who has had any 
experience with concrete street or road construction 
knows that for ease of manipulation it is necessary 
to use a httle more water in the concrete mixture 
than is required for the greatest strength of concrete. 
Until the advent of the Macon roller, the objections 
to this excess quantity of w^ater in the concrete could 
not be readily overcome, but with the roller method 
of finishing developed by Captain Gaillard much of 
the excess water is removed from the concrete in the 
process of rolling, while at the same time the concrete 
is considerably compacted. 

The result of using the roller was described in an 
article by A. N. Johnson, Consulting Highway Engi- 
neer of the Portland Cement Association, in the 
^^ Concrete Highway Magazine ^^ for April. Mr. 
Johnson says: ^^The effect of the roller is that of a 
rolling squeegee. It consolidates the top layer of 
the concrete and removes practically all of the sur- 
plus water. At the same time it takes out the slight 
uneven places in the surfaces which may occur, 
particularly if the pavement has not been struck by a 
template. The rolling should be continued until free 
water ceases to come to the surface.'' 

Mr. Johnson also described ^' Tests of Concrete 



MAKE AND HOW TO USE CONCRETE 99 

Slabs to Determine the Effect of Removing Excess 
Water Used in Mixing/' in a paper presented at the 
twentieth annual meeting of the American Society 
for Testing Materials. This paper was based on 
experiments made by finishing concrete slabs by a 
wood float and by the roller method. Tests were 
conducted at the Structural Materials Research 
Laboratory, Lewis Institute, Chicago, under the 
supervision of Mr. Johnson and D. A. Abrams, 
Professor in Charge at the laboratory, who collabo- 
rated in this work. The results of tests brought 
out the fact that slabs finished with the roller 
developed twenty per cent increase in strength over 
slabs merely hand finished. The appearance of 
broken slabs disclosed a marked difference between 
those finished with the roller and those finished with 
the hand float. The former had a distinctly denser 
appearance, which extended for at least half the 
depth of the slab. Highway engineers should not 
fail to take advantage of the disclosures made by 
these recent tests. 

Since field operations in concrete highway work do 
not permit the use of a concrete of the most desirable 
consistency with particular reference to the strength 
of the concrete, the roller method of finishing, which 
removes much of the excess water, is especially 
desirable. 

The Macon roller is not an experiment, as the 
nearly 300,000 square yards of superior concrete 
pavement in Macon, Georgia, show. Jilngineers 
elsewhere have recognized that there is something 



100 THE RANSOM K BOOK — HOW TO 

in the Macon finishing methods and have not been 
slow to follow the practice originated by Captain 
(iaillard. 

The Ransonie Concrete Machinery Co. manufac- 
tures the Macon Concrete Paving Roller. 

After the roller has been run over the surface two 
or three times, depending upon the consistency of the 
concrete, final finishing is then done with a belt, 
either canvas or rubber, eight to twelve inches wide, 
and operated by seesawing it back and forth across 
the concrete surface. The belt method secures a 
uniformit}^ of surface and one free from minor irregu- 
larities that cannot be obtained by hand-floating 
methods. The belt used is a little longer than the 
width of the pavement, so that workmen have six 
inches or more plaj^ in length to pull it backward and 
forw^ard across the concrete by handles attached to 
the belt. Use of the belt produces an ideal finish for 
concrete pavement, namely, the even but gritty 
texture which makes the characteristic non-skid 
concrete surface. 

PROTECTION OF FINISHED PAVEMENTS 
Curing of concrete pavements has much to do 
with their success. If the concrete is allowed to drj^ 
out the resulting surface will not be highly resistant 
to wear. As soon as the concrete can be covered with 
earth without marring its surface, this should be 
applied to a depth of two inches or more and should 
be kept wet b}^ frequent sprinkling for a week or ten 
days. Another and still better method, where avail- 



MAKE AND HOW TO USE CONCRETE 101 

able, is the ponding method. This consists of flooding 
.the finished pavement by building dikes or dams on 
the slabs so that water will stand at least two inches 
deep over the crown of the pavement. Concrete 
pavement construction should not be carried on 
during weather when freezing temperatures are 
likely to prevail. Concrete pavements should not 
be opened to traffic until they are at least three weeks 
old and preferably a month old. During cold 
weather concrete hardens slowly, and only experience 
can determine how long traffic should be kept off the 
pavement after finished. 

ESTIMATING FOR THE CONTRACTOR 

GENERAL 

For accurate work every one should compile his 
own estimating data. Figures that have been com- 
piled by others may be of some value in estimating 
the cost of a particular piece of concrete work, but 
it is almost always true that there are some details 
lacking that make the figures of some one else mis- 
leading or insufficient. They usually fail to give an 
idea of all conditions associated with the work, so a 
contractor who accepts the figures of some one else 
as the basis of an estimate is likely to find that after 
receiving a contract some of his figin^es represent a 
price below cost. Every contractor should keep 
data tables of his own with details of the job, which 
will help to an accurate comparison with other 
similar jobs. Contractors are frequently asked to 



102 THE RAN SOME BOOK — HOW TO 

give an approximate estimate of the cost of a certain 
piece of work. This is quite different from an. 
estimate which calls for exact details. Buildings of 
a certain class average in cost a certain price per 
cubic foot of volume. Knowing this, approximate 
figures can be given that will furnish a fair idea of 
what a finished structure w^ill cost. 

Most important among the items that influence 
the cost of any piece of work are materials, labor, 
location of the work, transportation conditions, 
weather, character of the work, rapidity of construc- 
tion, equipment required, incidentals, and finances. 



MATERIALS 

Materials used in concrete work wdll be in general 
from twenty to seventy per cent of the work's total 
cost. Forming such a large item, errors in estimating 
have considerable effect on probable profit. If 
materials are not up to standard in quality, strength, 
and durability, all the work will be affected adversely 
and the contractor may be compelled to remove and 
rebuild a portion of it, thus involving a loss greater 
than his figured profit. These conditions have often 
been responsible for the financial ruin of a contractor. 

On concrete work the contractor is the manu- 
facturer. On work where steel and wood figure 
largel}^, finished material is supplied to the job and 
the contractor is mcrel}^ a builder. In the case of 
concrete construction he must know the materials 
he is to use and how to combine them for best results. 



MAKE AND HOW TO USE CONCRETE 103 

He is both a manufacturer and a builder. He must 
know the suitabihty of aggregates, must know the 
principles of good concrete practice, and must see 
that good materials and good practice are used; 
otherwise he cannot guarantee the finished work. 
Often an owner, engineer, or architect compels a 
contractor to use a material or method w^hich is not 
perhaps in favor from the standpoint of specifications, 
yet the contractor may be held responsible for the 
resulting work. The contractor should safeguard 
himself against such happenings by seeing that the 
specifications after which he is working properly 
relieve him from responsibility when compelled to 
follow variations from what is in general recognized 
as better practice. 

The item of waste must be considered in esti- 
mating. Certain quantities of cement and aggregate 
will be wasted in spite of the best handling. 
Economy of use and care in handling will reduce 
waste to a minimum. Labor varies in cost within 
wide range; just at present it is particularly variable. 
Constant supervision must be exercised to keep 
working forces efficient. Labor cost can be esti- 
mated accurately only by knowing from long experi- 
ence the amount of work which certain classes of 
laborers can be depended upon to perform within a 
given time and under various conditions. Each job 
is a pro})lem in itself from the labor standpoint. 
The available su})ply of men, whether they live near 
or far from the work, (he possibilily of labor 
disturbances, all must be discounted in advance. 



an THE RAN SOME BOOK — HOW TO 

LOCATION 

Progress of the work, time of completion, and cost 
are influenced by the location of the work with 
respect to supplies of materials and labor. If the 
work is in a locality where all labor needed can be 
obtained readily, there will be one labor situation to 
figure upon. If labor must be imported, then the 
supply is likely to be variable and more costly. 

TRANSPORTATION 

Distance from base of supplies and the condition 
of roads and availability of teams or motor trucks 
must be taken into consideration. With good roads 
there is probably no question but that motor trans- 
portation is most dependable. If large quantities of 
materials are required, speed of -construction is 
limited by transportation facilities. Unless materials 
can be delivered and stored on the site in large 
quantities before work commences, then deliveries 
must be carefully planned so that there will be an 
uninterrupted supply to keep men and equipment 
always busy. 

A team or motor truck can be depended upon to 
haul a certain tonnage a given distance per hour on 
a certain kind of road over certain grades. The net 
results will vary in accordance with variation of 
average conditions. If roads that are good in fair 
weather quickly become bad in bad weather, 
transportation costs will rise rapidly; in fact, the 
work may have to be suspended because materials 
cannot be moved. 



MAKE AND HOW TO ' USE CONCRETE 105 

WEATHER CONDITIONS 

Weather conditions play an important part in the 
cost of construction. Storms are often more pro- 
longed than expected, especially where the job is one 
extending over a long period of time, and the average 
conditions considered when estimating may turn out 
quite contrary to what will be actually experienced 
during the work. 

CHARACTER OF WORK 

In reinforced concrete construction cost of 
materials is secondary to labor. On mass concrete 
work, such as foundations, conditions are reversed. 
Certain kinds of work require complicated and costly 
form work. In other cases forms are relatively 
cheap. Variations in methods of placing concrete 
involve greater or less cost. Labor-saving devices 
can often be economically adopted, but experience 
is necessary to enable decision as to whether or not 
more machinery or devices on the job will pay. 

RAPIDITY OF CONSTRUCTION 

There is a limit to the speed with which concrete 
work can be carried on. Speed is considerably 
limited in cold weather. If work is speeded too much 
at any time the structure may collapse. Such con- 
ditions often compel a larger investment in forms or 
form material where otherwise it might be possible^ 
to make more frecjueiit use of fewer sets of forms. 

Machine mixing is always i)referable. An ap- 



10() THE RAN SOME BOOK — HOW TO 

proved durable type of batch mixer is an indispens- 
able jxirt of every concrete contracting equipment. 

Forms should be considered as part of the equip- 
ment. After it is known how long service forms 
or form lumber will give, the amount of form cost 
to charge to any particular job can readily be 
determined. 

All equipment must be kept in serviceable condi- 
tion. In spite of best care, however, there is constant 
depreciation, and eventuallj^ equipment must be 
replaced. Several methods are used for charging ofif 
the cost of equipment and setting aside a certain 
sum weekly or monthly for replacement. Most 
contractors agree that if 0.17 per cent of the total 
cost of equipment is charged to each day's work, 
sufficient funds will be accumulated to cover 
maintenance and replacement. 

It costs mone}^ to move equipment about the job 
or from one job to another. Cost of erecting and 
dismantling the plant must also be determined and 
included in the estimate. 

EMPLOYERS' LIABILITY 

In some States the laws hold employers liable for 
accidents incurred by their employees. Liability 
insurance should be carried for the contractor's 
protection in this way. Its cost varies for different 
classes of work,- but should be determined, so that 
the proper charge can be made for it in estimates. 

Contractors often have to accept as payments 
various kinds of commercial paper, such as bonds, 



MAKE AND HOW TO USE CONCRETE 107 

warrants, notes, etc., instead of cash. Frequently 
such securities have a variable market value. An 
understanding should be reached before bidding as 
to how payments are to be made, and if securities 
instead of currency are to be accepted the con- 
tractor should make arrangements for disposing of 
them as necessary. A contractor might estimate a 
job at $5,000, including a profit of $500. If compelled 
to take bonds that can be sold for only 90 cents on 
the dollar he therefore would receive only $4,500 
actual cash, so would have no profit. 

He should know exactly what capital he needs to 
finance the job with respect to the credit he can 
secure on materials, equipment, or other supplies, 
and time payments for purchases, so that he will at 
no time use up, even temporarily, his working 
capital. 

ESTIMATING 

Cement can be estimated accurately, therefore it 
is not necessary to increase the quantity estimated 
for. There should, however, be added something to 
the actual cost per barrel to cover the handling of 
sacks. The percentage of sacks lost is largely de- 
pendent upon how they are handled on the job. It 
is safe to say that the average loss amounts to about 
10 cents per barrel in sacks, labor of handling them, 
and accounting for them. This inchidos return 
freight, etc. 

AGGREGATES 

Aggregates ai"(^ sold by wcMght oi- by the cnibic 
yard. A unit weight is adophMl niul ordtM's ixmhmnimI 



108 THE RANSOME BOOK — HOW TO 

in cubic yards are converted into equivalent weight. 
The unit weight is often adopted by agreement, so 
the volume may be only approximately correct. If 
aggregates are hauled a considerable distance and 
transferred from railroad cars to wagons there will 
be some loss in weight and some actual loss on the 
job because of materials getting mixed with or 
tramped into the dirt. Losses can generally be 
figured as not to exceed ten per cent for each class of 
aggregate. 

WATER 

Often contractors fail to include cost of water in 
estimating. Sometimes it costs comparatively noth- 
ing, but frequently its cost is considerable. Quantity 
of water required can be figured at from 40 to 50 
gallons per cubic yard for concrete only. In addition, 
however, water required for operating mixers, 
engines, wetting forms, sprinkling concrete, sprink- 
ling subgrade in pavement work, etc., will increase 
the quantity required to 100 gallons per cubic yard. 
For mass concrete 60 to 75 gallons per cubic yard is 
a safe estimate. For slab floors, sidew^alks, pave- 
ments, from 125 to 165 gallons per cubic yard may 
be required, depending upon the season of the year. 
Water may have to be hauled or piped a considerable 
distance. Often water can be contracted for from 
city water mains. In such case, charges are fre- 
quently based on a rate of from 1 2 to 1^/^ cents per 
square yard of concrete pavement. 



MAKE AND HOW TO USE CONCRETE 109 

FORMS 

As mentioned elsewhere, foims may cost to erect 
from $15 to $35 per thousand feet board measure of 
lumber used. The contractor should keep accurate 
cost of forms for many classes of jobs, so that event- 
ually approximate cost can be determined for any 
job. 

REINFORCING STEEL 

At present steel is much more expensive than ever 
before. Estimates should be increased ten per cent 
over actual requirements, to cover wastage from 
cutting, shaping, etc. Cost of steel is generally 
figured in place, and this cost is made up of the 
actual cost of the material plus hauling, loading, 
bending, where necessary, placing, etc. 

HAULING CHARGES 

Hauling charges include cost of loading and 
unloading, both working and waiting time of team 
and driver, and team time in travel. The less lost 
motion there is, by just so much can hauling charges 
be reduced. Rate of team travel is based usually 
on from twenty to twenty-two miles actual distance 
in ten hours on average roads and grades with 
occasional bad spots. If there are difficult places 
en route two or more teams should be run together 
so that one can be used as a ^'snatch" team if the 
other gets stalled. 

A laborer will load loose material by shoveling 
from ground of car into a wagon about as follows: 



no 



77/ /i" RAN SOME BOOK — HOW TO 



(lood Working 
CoiHlitions aiKl 
without D<lav.- 



IiH'xiK'ritncod 
Workman and 
Delays. Con- 
i-orvative Esti- 
mating 



Materials Shoveled, Working Continuously 



Cu. Yd. 
per hr. 



Tons 
per hr. 



Cu. Yd. Tons 
per hr. per hr. 



From ear to wagons — Crushed Stone . . . 

From car to wagons — Gravel 

From oar to wagons — Sand 

From ground to wagonS' — Plowed Clay, some 

Chunks and Stones 

From ground to wagons — Plowed Loam 
From ground to wagons — Crushed Stone . 
From ground to wagons — Sand 



2.0 
2.0 
2.5 



3.0 
3.0 
3 . 75 



2.0 


2.5 


1.5 


1.9 


2.5 


3.0 


2.0 


2.5 


3.0 


4.5 


2.0 


3.0 


4.0 


6.0 


3.0 


4.5 



A team will haul about two cubic yards on a good 
road, and about half that amount over excavated or 
soft ground. Sometimes it is necessary to use a 
''snatch" team to haul material economically under 
some conditions. 

A yard of material can be loaded by shovel gangs 
in about six minutes. As team time runs high it is 
often profitable to employ a loading device or extra 
wagons which can be run in place by a ''snatch'' 
team or laboring gang. 

The following is based on six-minute loading time 
and volume loaded of 1 yard : 
Slat wagons: 

1. Load and dump (1 cubic yard), eight minutes. 

2. Hitch, dump, and unhitch (1 cubic yard), four 
minutes. 

Contractor's dump wagon: 

1. Load and dump (1 cubic yard), six minutes. 

2. Hitch, dump, and unhitch (1 cubic yard), two 
minutes. 



MAKE AND HOW TO USE CONCRETE 



111 



A team will haul on 


Pounds 


Aggregate 
cu. yds. 


Sacks 
Cement 


Excavation 
cu. yds. 


Very poor earth road 

Poor earth road 

Good hard road 

Good macadam or paved road 


2,000 
2,500 
4,000 
6,000 


0.67 
0.835 
1 . 33 

2.00 


20 
25 

40 
60 


.8 
1.0 
1.6 
2.4 



2,000 feet of travel will take ten minutes, giving a 
haul length of 1,000 feet. For each 1,000 additional 
feet of loaded haul ten minutes should be added to 
time en route. 



HAULING CEMENT 

A team will haul loads itemized in the foregoing 
table at ten minutes per 1,000 feet of loaded 
haul. 

Loading near stock pile takes about three quarters 
of a minute of labor per sack of cement or three 
minutes per barrel. Unloading under similar condi- 
tions takes the same amount of time. The time 
which a team is delayed while doing this is dependent 
on the number of laborers employed. It may there- 
fore be profitable to have additional wagons at one 
or both ends of the haul, so that the teams will not 
be delayed. Time consumed in changing wagons 
twice may be taken as five minutes. To the net 
cost of cement when handled in sacks there should be 
added a charge of ten cents per barrel to cover 
handling empty sacks, shipping them back, and the 
loss of sacks which cannot be redeemed. 



112 THE RAN SOME BOOK — HOW TO 

SUMMARY HAULING CHARGE 

Lal)()r time in loading yards 

hours at $ per hour 

Loss of team time waiting or changing wagons 
minutes at $ per minute 



Team time consumed in unloading, 
minutes at $ per minute 



Labor time consumed in assisting unloading 

minutes at S per minute 

Team time hours en route at S 



per hour Total expense for hauling 

yards to job 

Cost per cubic yard for hauling to job 



(Superintendence and overhead to be added to 
total estimate.) 



EXCAVATING AND GRADING 

Dirt or clay when loosened wdll increase in volume 
from tw^enty to thirty-five per cent and go back in 
fill to its original volume if compacted to the same 
degree as in its natural condition. Earth will shrink 
as much as ten per cent of its original volume if when 
transferred to another location it is compacted with 
roller. 

Loosening Material 
L With Plow: 

(a) One plow, team and driver, and one 
helper will loosen 35 cubic yards ordinary earth 
per hour. 



MAKE AND HOW TO USE CONCRETE 113 

(6) One plow, team and driver, and one 
helper will loosen 15 to 20 cubic yards of dirt 
or clay road surface per hour. 

(c) A pick-pointed plow, four horses, two 
drivers, one helper will loosen 19 yards of extra 
tough surface per hour. 

2. Picks. 

(a) One man will loosen as follows per hour : 
33^2 yards of average earth. 
2 yards of tough clay. 
^ yard of hardpan. 

3. Moving Material. 

Scrapers limit haul '*Drag" 200 feet. * 'Wheel' ' 500 feet 

Drag 25 ft. haul, 1 scraper, 1 team and driver, 1 helper move 60 yd. per day 
Drag 50 ft. haul, 3 scraper, 3 team and driver, 1 helper move 150 yd. per day 
Drag 100 ft. haul, 3 scraper, 3 team and driver, 1 helper move 120 yd. per day 
Drag 200 ft. haul, 3 scraper, 3 team and driver, 1 helper move 105 yd. per day 
Wheel 200 ft. haul, 3 scraper, 3 team and driver, 1 helper move 120 yd. per day 
Wheel 300 ft. haul, 3 scraper, 3 team and driver, 1 helper move 100 yd. per day 
Wheel 400 ft. haul, 3 scraper, 3 team and driver, 1 helper move 80 yd. per day 
Wheel 500 ft. haul, 3 scraper, 3 team and driver, 1 helper move 65 yd. per day 

MIXING, PLACING, AND HANDLING CONCRETE 

WITH NOT LESS THAN MINIMUM NOR MORE 

THAN MAXIMUM SIZED GANGS 

1. Mixing by hand 0.2 yards per man per 
hour 

2. Stationary mixer with elevated loading 
platform, wheeling short distance to mixer, | 
cubic yard per man supplying material to 
mixer and operating mixer. 

3. Movable mixer with moclianicallv lioistod 



114 THE RAXSOME BOOK — HOW TO 

loadiiif;* skip, 1 to 1| cubic yards per hour per 
inaii sui:)plyin^' materials to mixer and operat- 
ing mixer. 

Following is shown the amount of "quaky" con- 
sistenc}^ concrete which has a tendency to slop over 
from wheelbarrows on le\Tl or average grades from 
mixer to place of depositing, and also includes labor 
cost of extra men necessary to place and spread or 
spade the concrete. 

25 foot haul 0.75 cubic yards per man per hour 
10(3 foot haul 0.50 cubic yards per man per hour 
150 foot haul 0.40 cubic yards per man per hour 
200 foot haul 0.33g cubic yards per man per hour 
225 foot haul 0.30 cubic yards per man per hour 

The above are safe estimates where the crew is 
balanced so that no portion is materiallj^ delaj'ed. 

When the mixer can be kept close to the place 
where concrete is being deposited the only labor 
required is that to spread the concrete. One man 
can handle up to 2.5 cubic yards per hour; two men 
can generally do more than twice that done by one 
man, and four men can handle from 12 to 16 cubic 
yards per hour, depending on the nature of the work. 

When concrete must be hoisted above the level of 
the mixer the problem is simple to solve; but it is 
difficult to give smy general cost data because of the 
variation in character of plants and the many 
different heights to which the concrete is raised. 
The plant, however, when once chosen remains 
constant in daily operating cost, while its output is 
dependent upon time of operation. 



4 



MAKIE AND HOW TO USE CONCRETE 115 

For example : A one-horse operated winch is used 
to hoist concrete in silo work. The quantity of con- 
crete deposited each day must be the same, as the 
forms must be filled once each day. As the height of 
hoist increases, the time consumed in raising the 
bucket of concrete increases; the horse must work 
more hours to raise the same amount of concrete and 
the time of the gang is lengthened accordingly. Even 
with engine hoist the same results follow. 

When the quantity of concrete to be deposited in a 
given period is variable, the cost will vary unless the 
size of the gang is kept adjusted to working 
conditions. 

Several types of ordinary elevator hoists are 
available. Their output may be estimated by 
dividing one fourth the loaded speed in feet per 
minute into the height to which operating. There 
is also an endless chain hoist with liigs which catch 
the barrow or wheel carts, carry them to the required 
height, automatically set them off, and return the 
empties in the same manner. With this equipment 
the output may be maintained constant by adjusting 
the number of carts or barrows; then the cost of 
raising concrete would be the cost of operating the 
hoist together with accessories. 

Concrete is sometimes delivered by gravity spout 
or chute, but here the hoist problem is the same, 
and the spout substitutes the conveying of concrete 
by barrows or carts from the elevator to place where 
deposited. 

For general estimating the following cost of con- 



116 THE RAN SOME BOOK — HOW TO 

Crete work complete may be used in normal times. 
These figures include forms, profit, and all other 
necessary items. 

Concrete in large masses $4 to $6 per cubic yard 
where few^ forms enclose a large quantity of concrete. 
For example: Engine foundations, pavement foun- 
dations, building foundations, bridge abutments, and 
walls two feet or more thick, of medium height. 

Plain concrete walls from eight to sixteen inches 
thick, and other plain concrete construction re- 
quiring simple form w^ork and some steel reinforce- 
ment for temperature stresses, $6 to $8 per cubic 
j^ard. 

The same class of work, but more complicated, up 
to $12. 

Reinforced concrete work, including bridge floors, 
building construction, etc., $12 to $20, with a 
general average figure of $15. 

"^Concrete sidewalks, $7 to $9 per cubic yard. 

*Concrete street pavements, $7.50 to $9.50 per 
cubic yard. 

SURFACE TREATMENT OF CONCRETE 

There being practically no limit to the variation 
possible in the treatment of concrete surfaces, 
naturally the cost must often resolve itself into the 
known items, such as materials required, scaffolding, 
and the unknown quantity of labor, which must be 



♦Note: For his own information the contractor must figure the volume of 
concrete. As pavement specifications may vary in stating the thickness required, 
the contractor will then reduce his cubic-yard cost to a square-yard basis, as paving 
costs are usually expressed in this way. 



MAKE AND HOW TO USE CONCRETE 



117 



conservatively estimated from the contractor's know- 
ledge of the surface area that can be treated in a 
given time by the men available. Hence the con- 
tractor must have personal knowledge of the ability 
of the men who will actually do the w(3rk or feel 
certain that he can teach men to do it for the cost 
estimated. 

The following table gives the quantities of 
materials required for Portland cement exterior 
plastering of varying thicknesses: 

NUMBER OF SQUARE FEET OF WALL SURFACE 

COVERED PER SACK OF CEMENT, FOR 

DIFFERENT PROPORTIONS AND VARYING 

THICKNESS OF PLASTERING 



Pro- 
portions 
of 


MATERIALS 


TOTAL THICKNESS OF PLASTER 


Sacks 
Cement 


Cu. Ft. 
Sand 


Bushels 
Hair* 


3^ in. 


%m. 


1 in. 


VA in. 


13^ in. 


Mixture 


Sq. Ft. 
Covered 


Sq. Ft. 
Covered 


Sq. Ft. 
Covered 


Sq. Ft. 
Covered 


Sq. Ft. 
Covered 


1 
1 
1 
1 
1 


1 

VA 

2 

3 




1 

I'A 

2 

2H 

3 


Vs 
Vs 


33.0 
42.0 
50.4 
59.4 

G7.8 


22.0 
28.0 
33.6 
39.0 
45.2 


16.5 
21.0 
25.2 
29.7 
33.9 


13.2 
16.0 
20.1 
23.7 
27.1 


11.0 
14.0 
16.8 
19.8 
21.6 



*Used in scratch coat only. 

Note. These figures are based on average conditions and may vary 10 per cent 
either way, according to the quality of the sand used. No allowance is made for 
waste. 



After having decided upon the thickness of the 
wall plaster and the mixture to be used, it is easy to 
determine the totiil materials recjuired for coveriui; 
a given wall surface, since the table shows the number 
of square feet of surface covered by the mortar re- 



ILS THE RAN SOME BOOK — HOW TO 

suiting from one sack of cement. Waste can be 
reduced by placing a plank on the ground at the base 
of the wall to catch plaster that falls. Such plaster 
should never be used after it has once begun to 
harden, and therefore should not be allowed to 
accumulate but should be gathered up promptly 
and remixed with the mortar already prepared. . 
Cement plaster should not be mixed in batches 
larger than are needed for immediate use, otherwise 
some of the mortar may begin to harden before it 
can be used and must be thrown away. 

Cement stucco work generally costs from $1.50 
to $1.75 per square yard, including building paper 
and wood or metal lath, the metal lath costing a 
little more than the wood. The two-coat smooth 
work often costs less than $1.50. When granite or 
marble chips are used in the rough exposed dry or 
other dash, the extra cost of such materials may 
raise the price to $1.75 or slightly more. 

When the form face is plastered with chips or 
colored pebbles backed by the regular wall con- 
crete, and after the forms are removed, the surface 
film of cement is brushed or washed with a weak 
solution of acid, the extra cost generally runs from 
five to ten cents per square foot of surface. 

Concrete wall surfaces are treated by one coat of 
cement mortar, smooth or dash finish, at a cost of 
approximately five cents per square foot. Concrete 
surfaces are frequently tooled to reveal the aggregate. 

The tooth-axed surface is probably the most 
widely known. This work is done by lightly chipping 



MAKE AND HOW TO USE CONCRETE 



119 



with a tooth-ax and thus breaking away the surface 
skin of the concrete. The work is generally done in 
panels or to produce designs with borders or certain 
areas left smooth. The smooth surfaces are rubbed 
with cement grout and a carborundum stone and 
pointed up. The work generally is contracted for at 
from six to seven cents per square foot of exposed 
area of the building with the addition of all areas to 
be treated at angles to the surface. Stone cutters are 
preferable for this work and one man will cut from 
80 to 100 square feet per day of eight hours or over, 
approximately 150 square feet of surface in like 
time. 

BRICKWORK— WALLS 

8 f in. by 2 f in. by 4 in. brick {\- in. joints requires 12 cu. ft. of 
mortar per 1,000 brick. With a 1 cement 3 sand mix, 1 barrel cement 
per 1,000 brick. Allowing for waste 1.25 barrels cement per 1,000 
brick. 1,000 brick will lay 475 square feet of 12 in. wall. 

CONCRETE FOUNDATIONS— WALLS, ETC. 



1 cu. ft. 


Sacks of 


1 cu. yd. 


Bbls. of 


Concrete 


Cement 


Concrete 


Cement 


1:1:1 


. 5404 


1:1:1 


3.375 




1^:3 


.2808 




13/2:3 


1.895 




2:4 


.2220 




2:4 


1.498 




2^:5 


. 1848 




2^:5 


1.247 




3:6 


. 1570 




3:() 


1. ()()() 



120 



THE RANSOMS BOOK — HOW TO 



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MAKE AND HOW TO USE CONCRETE 



121 






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122 



THE RANSOM E BOOK — HOW TO 



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MAKE AND HOW TO USE CONCRETE 



123 



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MAKE AND HOW TO USE CONCRETE 



125 



QUANTITIES OF PORTLAND CEMENT, SAND, AND 

PEBBLES OR CRUSHED STONE FOR 100 SQUARE 

FEET OF CONCRETE 10 INCHES THICK, 

EQUAL TO 3.08 CUBIC YARDS 



Proportions 



Quantities 



Sacks 


Cu. Ft. 


Cu. Ft. 


Sacks 


Cu. Yd. 


Cu. Yd. 


of 


of 


Pebbles 


of 


of 


Pebbles 


Cement 


Sand 


or Stone 


Cement 


Sand 


or Stone 




1 




60.2 


2.23 






IVl 




47.7 


2.65 






2 





39.4 


2.92 




1 


2^ 




33.8 


3.13 






3 




29.5 


3.29 


, 


1 


1 


1 


41.7 


1.54 


1.54 




I'A 


3 


23.4 


1.30 


2.60 




2 


3 


21.5 


1.59 


2.38 




2 


4 


18 5 


1.37 


2.7i 




2K 


4 


17.2 


1.59 


2.54 




23^ 


5 


15.4 


1.43 


2.86 




3 


5 


14.2 


1.58 


2.64 



Note. These quantities can be safely used for estimating, 
ordering materials, and, after the work is done, as a check to prove 
that the required quantity of cement has been used. Actual quantity 
of materials used in the concrete should not vary more than ten per 
cent above or below the quantities given in the table. 

This table can readily be used for any concrete 
structures which can be measured in area and which 
are of uniform thickness over any considerable area, 
such as walls, floors, and walks. 

The following examples illustrate the use of the 
table : 

Example 1.. Required the quantity of matorinls for a 12 inch 
thick basement wall, 6. feet 5 inches high al)ovc footing, for a hous(^ 
25 feet by 40 feet outside dimensions. The footing 1 foot () inches 
wide and (> inclu^s thick. ConcnHt^ |)r()p()rti()iied 1:3:5. 



12() THE RANSOME BOOK — HOW TO 

Wall: 

Length of wall 25+254-39+39 = 128 ft. 

Height of wall ft. 5 in. =GiV =6.417 ft. 

Area of wall = 128X6.417 =82*^1.4 sq. ft. 

Thickness of wall = 12 in. 

(Quantities of materials for wall concrete: 

Factor for multiplying units in 

table = 821.4 12 

X — = 8.214X1.2=0.S5(>8; 

100 10 

Take 9.86 

Sacks of cement = 14.2X9.86 = 140.0 

Cu. yd. of sand = 1.58X9.86 = 15.6 

Cu. yd. of pebbles or crushed stone = 2.04X9.80 =26.0 

Footing : 

Length of footing = 25.5+25.5+37.5+37.5 = 120 ft. 

Width of footing = 1 ft. 6 in. = 1y*V = 1''^ ft. 

Area of footing = 126X1.5 = 189 ft. 

Thickness of footing = 6 in. 
Quantities of materials for footing: 

Factor for multiplying units in the 

table =189 6 

— -X — = 1.89 X.6 = 1.134 = 1.13 
100 10 

Sacks of cement = 14.2 X 1 . 13 = 16.0 

Cu. yd. of sand =1.58X1.13 = 1.8 

Cu. yd. of pebbles or stone =2.64X1.13 =3.0 

Total quantities of materials: 

Sacks of cement = 140 + 16 = 156.0 

Cu. 3^d. of sand =15.6 + 1.8 = 17.4 or 17.5 

Cu. yd. of pebbles =26.0+3 =29.0 

Example 2. Required the quantities for a concrete floor for a 
basement. Interior dimensions of the basement 23 feet by 38 feet. 
Floor 5 inches thick over all, with 4 inch base of concrete propor- 
tioned 1:2J^:5, and 1 inch wearing course composed of cement 
mortar proportioned 1:2. 

Area of floor =23X38=874 sq. ft. 

Factor for multiplying quantities in table for 

base =874 4 

— X— =8.74X.4=3.5 
100 10 



MAKE AND HOW TO USE CONCRETE 



127 



Quantities of materials for base concrete : 

Sacks of cement = 15.4X3.5 =54.0 

Cu. yd. of sand =1.43X3.5=5.0 

Cu. yd. of pebbles or stone =2.86X3.5 = 10.0 

Factor for multiplying quantities in table for 

wearine; surface = 874 1 

^ X-=8.74X.1=.9 

100 10 

Quantities of materials for wearing surface mortar: 

Sacks of cement =39.4 X. 9 =35.5 

Cu. yd. of sand =2.92 X. 9 =2.6 cu. yd. 

Total quantities of materials for floor: 
Sacks of cement = 54.0+35.4 =89.5 
Cu. yd. of sand =5.0+2.6 = 7.6 or 7.5 
Cu. yd. of pebbles or stone = 10.0 



SURFACE AREA (IN SQUARE FEET) OF CONCRETE 

SLABS OR WALLS OF VARIOUS THICKNESSES 

AND PROPORTIONS THAT CAN BE MADE 

WITH ONE SACK OF CEMENT 



Thickness 




Concrete Mixture 




of Slab 








or Wall 












in inchos 


1:2:3 


1:2:4 


1:2^:4 


1:2^:5 


1:3:5 


3 


15.52 


17.88 


19 42 


21.77 


23.2 


3M 


13.31 


15.33 


16.65 


18.67 


19.9 


4 


11.64 


13.41 


14.56 


16.33 


17.4 


43^ 


10.36 


11.93 


12.96 


14.53 


15.5 


5 


9.31 


10.73 


11.65 


13.06 


13.9 


5>^ 


8.46 


9.74 


10.58 


11.86 


12.6 


6 


7.76 


8.94 


9.71 


10.88 


11.6 


CyVz 


7.18 


8.27 


• 8 98 


10.07 


10.7 


7 


6.65 


7.66 


8.33 


9.33 


9.9 


8 


5.82 


6.70 


7.28 


8.16 


8.7 


10 


4.66 


5.36 


5.83 


6.53 


6.9 


12 


3.88 


4.47 


4.85 


5.44 


5.8 


14 


3.32 


3.83 


4.16 


4.66 


4.7 


16 


2.91 


3.35 


3.64 


4.08 


4.3 



I2S TIIK ILWSOME BOOK IJOW TO 
WEIGHTS AND VOLUMES 

Porllaiul ('(MiKMit \veiji;lis jkt barrel, lu^t 376 lb. 

Portland cement weighs per bag, net 94 lb. 

Natural cement weighs per barrel, net 282 lb. 

Natural cement weighs per bag, net 94 11). 

Loose Portland cement averages per cubic foot about 92 lb. 
\\'eight of paste of neat Portland cement averages per 

cubic foot about 137 lb. 

Volume of paste made from 100 lb. of neat Portland 

cement averages about 0.86 cu. ft. 

Weight of Portland cement mortar in proportions 

1: 2J/^ averages per cubic foot 135 lb. 

Weight of Portland cement concrete averages per cubic 

foot about 130 1b. 

Cinder concrete averages 112 lb. 

Conglomerate concrete averages 150 lb. 

Gravel concrete averages 150 lb. 

Limestone concrete averages 148 lb. 

Sandstone concrete averages 143 lb. 

Trap concrete averages 155 lb. 



MAKE AND HOW TO USE CONCRETE 



129 



.# 





RANSOME BANTAM MIXER 



The Ransome Bantam Mixer is of the low charging type 
and is regularly equipped with platform and runways. 
The drum has a capacity of 10 cu. ft. of loose material and 
will produce approximately 6 cu. yd. of concrete per hour. 
A gasoline engine of 3 H.P. is furnished, amply protected 
from the weather bv a ste(4 roof and side curtains. 



WRITE FOR RANSOME BANTAM BOOKLET 



i:^o 



THE h'AXSOME BOOK — HOW TO 




\ '\¥ 



RANSOME BANTAM SENIOR 

The Ransome Bantam Senior Mixer is built along the 
same general lines as the Bantam, except that it is regularly 
furnished with a side loader, automatic water tank, and 
4 H.P. gasoline engine. The output is therefore increased 
to lYi c'u. j'ds. of concrete per hour. 

WRITE FOR RANSOME BANTAM BOOKLET 



MAKE AND HOW TO USE CONCRETE 131 




RANSOME BANTAM JUNIOR 

FARMERS' TYPE 

The Ransome Bantam Junior Mixer of the Farmers is 
furnished with 23/2 H.P. gasoUne engine on a separate 
frame and trucks, so that the engine may be used for 
miscellaneous purposes about the farm or estate. The 
Contractors' Type of this machine has the engine mounted 
on mixer frame. Capacity of this mixer is 5 cu. ft. loose 
material per batch or 3 cu. yd. of concn^tt^ pvv liour. 



WRITE FOR RANSOME BANTAM BOOKLET 



\:V2 



THE UAXSOME BOOK — HOW TO 




RANSOME BANTAM PAVER 

The Ransome Bantam Paver is of the end load, end dis- 
charge type, having a capacity of 10 cu. ft. loose material 
per batch. It is equipped with open-end pivot hopper, 
10 ft. distributing chute, and 6 H.P. gasoHne engine, chain 
drive. The self-propelling traction as well as the porta- 
bility and light weight are attractive features of this 
machine. 



WRITE FOR ''RANSOME ROADS'' BOOKLET 



I 



MAKE AND HOW TO USE CONCRETE 



133 




RANSOME STREET PAVER — MODEL 10-E 

BUCKET AND BOOM TYPE 

The Ransome Road Paver, Bucket and Boom Type, is 
a distinctly high grade machine for heavy work. It is 
equipped with a 20 ft. distributing boom, on which runs an 
automatic dumping bucket. This mixer is equipped with 
steam power and has self-propeUing traction. It is made 
in one size only, capacity 14 cu. ft. loose material per 
batch. 



WRITE FOR ''RANSOME ROADS ' HOOKLET 



134 



THE RAN SOME BOOK ~ HOW TO 





^'^ -.x^, 






RANSOME SPOUT STREET PAVER 

The Ransome Road Paver, Spout Type, is made along 
the same lines as the Bucket and Boom Type, except that 
it is equipped with a distributing chute 15 ft. long. It is 
made in two sizes only, namely 14 and 30 cu. ft. of loose 
material per batch, with steam power. 



r 



WRITE FOR "RANSOME ROADS" BOOKLET 



MAKE AND HOW TO USE CONCRETE 



135 




J 



RANSOME MIXER WITH DIRECT-GEARED 
ENGINE 

WITH FIXED BATCH HOPPER 

The above illustration shows the Standard Type of 
Ransome Mixers equipped with Fixed Batch Hopper. 
These machines are made in sizes ranging from a batch 
capacity of 10 to 80 cu. ft. of loose material. Electric, 
steam, and gasoline pow(^r is furnished as desircnl. 



WRITE FOR -RAN SOME MIXERiS' BOOKLET 



THE RANSOM E BOOK — HOW TO 




RANSOME MIXER WITH COMPLETE STEAM 

PLANT 

DISCHARGE SIDE 

The a])Ove illustration shows the discharge side of the 
Ransome Mixer, Standard Type, on steel frame, with 
complete steam-power plant. These Mixers are equipped 
with cut steel gears and spUt adjustable bearings. Trac- 
tion rings have heavy steel bands welded and shrunk on. 



WRITE FOR -RAXSOME MIXERS'' BOOKLET 



MAKE AND HOW TO USE CONCRETE 



137 






RANSOME MIXER WITH ELECTRIC MOTOR 

WITH PIVOT HOPPER 

Due to simplicity in the direct connection of motors the 
above type of Mixer is very popuhir. Thv standard Haii- 
some side loader attachment is also illustrated, showing;' 
the cone friction hoist and oversize [)iv()t hopjx^r bucket. 
All motors are furnished with steel housings. 

WHITE FOR '' RANSOME ^.^IIXEHS'' BOOKLET 



138 



THE RANSOM E BOOK — HOW TO 




A COMPLETE l)arge plant is shown a1)ove, on which was 
u<ocl the following Ransonie equipment : Mixer, Steel 
'Power, Hoist Bucket, Tower Bin, Spoutinf!; and Boom 
Irons. This type of s])oulintt lavout is known as a "Boom 
Plant." 

WRITE FOR RAXSOME srolTIXd CATALOG 



MAKE AND HOW TO USE CONCRETE 



139 




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WRITE FOR RANSOM F Sroi TlXd CATAUHf 



140 



THE RAN SOME BOOK — HOW TO 



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Tr/?/7'A^ FOR RAX SOME SPOUTING CATALOG 



MAKE AND HOW TO USE CONCRETE 



141 




RANSOME-CANNIFF GROUT INJECTORS 

Ransome-Canniff Grout Injectors are designed for 
mixing and placing grout by compressed air. Cement and 
sand are delivered to the grout tank through the charging 
door, the proper proportion of water being added .^ The 
grout is mixed by allowing the compressed air to blow in 
at the bottom, which keeps the mixture ^'boiling" and 
prevents sand and cement settling into and choking the 
outlet pipe. During this operation th(^ blow-off valve is 
open. 

WRITE FOR RAN SOME PNEUMATIC BOOKLET 



142 



THE RAN SOME BOOK — HOW TO 




RANSOME-CANNIFF PNEUMATIC MACHINE 

The advantages of pneumatic machinery are many and 
far reaching. The mixer is located at a point where the 
aggregates can be handled most conveniently and economi- 
cally. The transportation of the mixed concrete to the 
forms is accomplished with the least possible expenditure 
of power and of material. The conveying pipe can be laid 
in almost any direction required. It takes up but little 
room — a highly essential feature in tunnel and subway 
work — and needs no heavy foundation supports or pre- 
pared runways of any sort. The concrete can be elevated 
to any required height or conveyed any reasonable dis- 
tance in a minimum of time. The concrete is placed 
through a short length of rubber hose of the same inside 



WRITE FOR RAN SOME PNEUMATIC BOOKLET 



MAKE AND HOW TO USE CONCRETE 



143 




RANSOME-CANNIFF PLACER ASSEMBLY 

diameter as the pipe. No hand spreading or tamping is 
necessary, as the concrete can be directed to the exact spot 
where it is needed. All labor between the mixer and the 
forms is eliminated except the two men handling the hose. 
Not only is the work accomplished more rapidly, but 
the cost is found in most cases to be considerably under 
that for any other method. The savings effected depend, 
of course, upon the particular type of work. In tunnel and 
subway construction it has amounted to over $2.50 per 
cubic yard of concrete placed. 



WRITE FOR RANSOME PNEUMATIC BOOKLET 



144 



THE RANSOME BOOK — HOW TO 




RANSOME HOIST BUCKETS 

Ransome Hoist Buckets are designed for use in towers 
where the work is too high to be reached by easy wheeling. 
The bucket is constructed along the most simple lines, 
catches and trips having been eliminated. A substantial 
bail, built up of angle irons, operates between two 5% in. 
wooden guides, and is furnished at the lower end with 
journals, in which rests the trunnion of the bucket proper. 
By removing a front guide at any point, automatic dis- 
charge of the bucket will take place through the space so 
left. 

WRITE FOR RANSOME EQUIPMENT BOOKLET 



MAKE AND HOW TO USE CONCRETE 145 




'1 




RANSOME CONCRETE BINS 

Ransome Concrete Bins are used in connection with 
Ransome Hoist Towers, either in conjunction with Ran- 
some Spouting or where the concrete is discharged directly 
into concrete carts. The sizes match up with the capa- 
cities of Ransome Mixers. 



WRITE FOR RANSOME EQUIPMENT BOOKLET 




1^<> THE RAN SOME BOOK — HOW TO 



RANSOME BIN GATES 

Of the three different styles 
of Kansome Bin Gates some 
one uill always be found suit- 
able for any position on the 
aggregate storage bins. The 

Vertical Bin Gate 

upper view shows the gate 
used for discharging stone and sand through the bottom 
of the bin; the center, gate 
for discharging through the 
bottom and delivering on one 
side or the other; and the 
lower illustration shows the 
gate for attaching to the ver- 
tical side instead of the bot- 
tom of the bin. Not only the Bottom Bin Gate 

quality of material used in Ransome Bin Gates, but 

i1il^«^ ^^^ ^^^^ ^^ workmanship, in- 

^HBB^ ^^^^^^ sures easy operation and per- 

^^^■fc^*^^ feet closure, even under the 

^^^H severe conditions of this 

^ir^ work. 

Front Bin Gate 



WRITE FOR RANSOME EQUIPMENT BOOKLET 




MAKE AND HOW TO USE CONCRETE 




147 



-rjzz:^""'^ 




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RANSOME CONCRETE CARTS 

Eansome Concrete Carts, when used in place of wheel- 
barrows for the distribution of concrete, cut down the 
number of wheelers to about one half, sometimes to one 
third of the original force. These carts hold 6 cu. ft., 
water measure. A special Ransome feature is the reversi- 
bility of the handles. These may be quickly changed end 
for end. The round contour of the cart bodies facilitates 
quick, clean dumping. Ransome Carts are furnished with 
or without legs. The legs are necessary for elevator work. 



Capacity 


Weight 


Diameter of Wheels 


Diameter of Axle 


6 cu. ft. 


255 lb. 


42 X 2 in. 


134 in. 



WRITE FOR RANSOME EQUIPMENT BOOKLET 



148 THE RANSOME BOOK 




RANSOME BAR CUTTERS 

Raxsome Bar Cutters are made from solid steel forgings 
— no cast iron whatever being used. They may cost a 
l)it more at the start, but they are by all odds the most 
economical in the end. The lightweight cutter will handle 
square and round stock up to % in., and flat iron 3f by 2 in. 
The heavier cutter will cut 13^ in. round or square stock, 
and flat iron up to % by 3}/2 i^^- For heavier stocks a 
power cutter is advisal^le. 



4 



WRITE FOR RANSOME EQUIPMENT BOOKLET 



INDEX 

PAGE 

Introduction v 

A Tribute ix 

Action of Sea Water on Concrete 58 

Aggregates 2 

Aggregates . . ' 86 

Aggregates 89 

Aggregates 107 

Aggregates for Wearing Course of Two-Course 

Pavement 88 

Back Filling 76 

Batch Mixers 28 

Brickwork — Walls 119 

Care of Reinforcement before Use 44 

Causes of Dusting 62 

Cement 89 

Character of Work 105 

Coarse Aggregate 87 

Concrete Estimating Tables and Examples .... 45 

Concrete Floors 61 

Concrete Foundations — Walls, etc 119 

Concrete — How to Make and Use it 1 

Concrete Tanks 64 

Concrete Walks 63 

Concreting in Cold Weather 54 

Consistency of Mixtures 29 

Cost of Form Work 38 

Design for Washing Plant 13 

Dimensions and Matkrlvls for Poofs ok Silos ()S 

Disi»osing of lOxcioss Matiokials S;") 

Drainage Sf) 

Employers' Liability 10(> 

Estimates on Specific Contracts 120 

Estimating 107 



1 



150 INDEX 

PAGE 

Estimating for the Contractor 101 

Excavating and Grading 112 

Excavation 7() 

Expanded Metal and Mesh Fabric 4:^ 

Field Practice in Concrete Road, Street, and Alley 

Construction 8:^ 

Fills 84 

Finishing Pavement Slabs at Joints 92 

Fire Resistance of Aggregates 22 

Forms 94 

Forms 109 

Forms and Footings 77 

Forms for Concrete 33 

Form Removal 40 

General 1 

Grading 84 

Grading of Aggregates 16 

Handling Materials on the Job 89 

Hauling Cement Ill 

Hauling Charges 109 

Importance of Bracing Forms 39 

Joints 91 

Location 104 

Location of Reinforcement 41 

Materials 102 

Materials Required for Concrete 125 

Materials Required for Plaster 124 

Materials Used as Reinforcement 42 

Materials for Silo Footing and Floors 68 

Materials Required for Sidewalks and Floors . . 122 

Material for Walls of Monolithic Silo 70 

Measuring Materials 29 

Measuring Materials 95 

Methods of Placing 49 

Mixed Aggregate 87 

Mixing 95 

Mlxing Concrete 2S 

Ml\in(j, Placing, and Handlin(j Concrete 113 

Ml\in(; Water 23 



% ; :-^5^^?^^, '^ 



INDEX 151 

PAGE 

Mixtures 77 

Monolithic Silos 76 

Placing Concrete 49 

Placing Concrete 96 

Placing Concrete and Steel Reinforcement ... 77 

Placing Concrete under Water 57 

Planning Forms Economically 37 

Principles of Reinforcing 41 

Proportioning Concrete Mixtures 24 

Protecting Finished Work 52 

Protection of Finished Pavements 100 

Quantities of Materials for Paving 90 

Quantity of Water 30 

Ransome Products 129-148 

Rapidity of Construction 105 

Reinforcing Concrete 41 

Reinforcement for Concrete Pavements 93 

Reinforcing Steel 109 

Requirements of Wood Forms 34 

Roofs 79 

Safe Load for Studs or Posts 36 

Screen Bank- Run Material 4 

Screening Pays 5 

Silos 66 

Size of Aggregates 23 

Specifications 83 

Square Feet per Sack of Cement for Wall Plastering 117 

Storage Requirements 2 

Striking Off and Finishing Pavement Surface . 97 

Summary Hauling Charge 112 

Surface Area of Concrete Slabs or Walls ... 127 

Surface Treatment of Concrete 116 

Table Giving Horizontal Reinforcement for Bloc^k 

Silos . r 73 

Table Civincj Lineal Vv.vvv of Tklxngle Mesh Rein- 
forcement 71 

Table of M.ateiu.xls Ke(m;ihi'^i) . 27 

Table of Mateiilm^s i-^oii Koof Slabs SO 

Table of Recommkndi^d Mixtuihos lM 



152 L\Dl!:X 

PAGE 

Table of Rein forcing fou I^oof Slabs 81 

Table of Tiuangle Mesh Helnfokcemext G9 

Table Showing Capacity of Silos in Tons (i? 

Table Showing Concrete Blocks Required 72 

Table Showing Method of Reinforcing Silos 71 

Table Showincj Thickness of Roof Slabs 79 

Time of Mixing 32 

Transportatiox 104 

Types of Floors ()2 

Types of Forms 3o 

Washing Aggregates 5 

Water 90 

Water . 108 

Weather Conditions 105 

Weights and Volumes 128 

Wetting or Greasing Forms 38 



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